DOOM Eternal Written Guide/Walkthrough for all collectables and secrets inc DLC.

Hello everyone.

Following on from DOOM 2016 I have decided to create another written guide, this time showing you the locations of ALL items/secrets/collectables etc. I'm hoping this is an improvement from my previous guide but feel free to comment and offer any feedback so i can correct any mistakes and change/update/improve this guide as much as possible.

I have tried to keep this as simple as possible but i'm pretty sure there will be plenty of mistakes. If you get stuck at any point please drop a comment and i'll do my best to help.

WARNING: This guide has many images so please allow them all to load first. Reload the page if the images are not showing correctly as Steam likes to act stupid at times.

So what are we going to find? ALL of the items listed below:

• Codex Pages
  
• Doomtoys (Toy collection)
  
• Album Vinyls (Album collection)
  
• Floppy Disks (Cheat code collection)
  
• Automaps
  
• Runes
  
• Data Logs
  
• Sentinel Crystals
  
• Sentinel Batteries
  
• 1UP Helmets (Extra Lives)
  
• Slayer Gate keys
  
• Weapon Mods
  
• Praetor Suit Tokens (Praetor suit points)
  
• Weapon Mastery Coins
  
• Blue Orbs and Other (Secrets)

• Youtube

• Check out my Doom Eternal Review
  
• This guide is image heavy.
  
• Each mission has been split into 2 parts due to steam limiting the amount of info that can be added to a section.

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NOTE: This mission is super easy and doesn't take long at all. Most of the items are easy to find so you shouldn't have a problem finding any of them even without my guide. This mission contains:

• 3 Doomtoys
  
• 3 Weapon Mods
  
• 1 Automap
  
• 6 Codex Pages
  
• 4 Extra Lives
  
• 1 Floppy Disks (Cheat codes)

Begin the mission and enter the first room that contains the chainsaw, at the back of the room on the left side is a breakable wall, break through and follow it around and up for your first doomtoy.
Continue the mission and you will come to your first weapon mod after climbing up from the large cube that you just moved.
In the next room clear the encounter and the gate will open to allow you to continue and also reveal your first codex page in the passage way.
NOTE In this area you will have 3 items to collect. After the cut scene you will be ported to a new area, the next codex page is straight ahead just before the entrance of the building in the direction of the mission, you can't miss it.
 
Immediately after the codex page climb up into the building and you will find another weapon mod, it's unmissable.
 
Immediately after the weapon mod, break the green wall and look up, you will see a ledge that you can climb up to and inside will be another doomtoy.
Continue the mission until you pick up the heavy cannon and just over the wall towards the mission marker you will find the automap, another you can't miss.

Make your way into the next area.

NOTE: In this area you will have 3 items to collect. As you enter the next area, climb the steel container on the left side to reach the upper part of the building, inside the building will be a wall you can break through which will allow you to drop down into the small room below containing your doomtoy. After this we will immediately move to the next item.
 
From the previous item take the left path up through the green lit doorway and head across the big hole in the floor to the opposite side, you will find a codex page around the corner and at the back of the room you can drop down into the hole to find an extra life in the room below.
Continue the mission and defeat the demons to drop the orange barriers, then break through the green wall and make your way around to the right side where there will be another wall you can break through which contains another extra life.
Now follow the mission through to the yellow door and into the tubes, when you reach the train wreck you will see a weapon mod next to the train carriage, you can't miss this as it's on the mission path.

Now keep going past the arachnotrons until you finish climbing the walls outside.

Once you have finished climbing a few walls head through the train carriage and follow the tunnel to find a codex page at the end just past the doorway.
After collecting the codex page you can now enter the nearby doorway and follow it through until you reach the stairway not too far away. Opposite the stairway is a crate you can use to climb up into the shaft and break the vent, inside will be a cheat code.
Now continue the mission until you reach the upper floor after climbing the wall inside the elevator shaft. When you exit the elevator shaft there will be another elevator to the left of you containing an extra life.
To access it you will need to go up to the next level and drop down inside from the upper elevator.
Continue and after exiting the building via the large window to the outside area head to the right side near the edge of map, you will see a yellow bar that you can use to swing across and collect the extra life that is hovering behind the overturned truck.
NOTE: In this area you will have 2 items to collect. Proceed with the mission and go through the portal into the citadel chamber. As you enter the main chamber immediately turn right and at the top of the steps you will find a codex page, from there go to the centre of the chamber next to the skull pedestal and opposite you in the passage next to the gate will be another codex page. That will be the final item for this mission.

Activate the skull pedestal to end the mission and head to the fortress of doom.

NOTE: This is your home and has many items to collect over the period of the campaign. You will not be able to find or collect everything immediately so you will need to come back after each mission and collect what you can with the resources available. But fear not as i will guide you to all items as we go through this. Current items available:

• 1 Sentinel Crystal
  
• 1 Arc Broadcast Log

This is a mission objective after completing mission 1, you cannot miss this but i will add it anyway so we can keep track.
You will gain this when activating the portal to mission 2, but if you want to listen to it you can activate the computer with the green screen located near the portal.

You are now ready to move on to mission 2.

NOTES: This mission is a little longer than the first with some hidden items that are not part of any collectables, but we will collect them anyway. You will also find your first slayer gate here. This mission contains:

• 7 Extra Lives
  
• 7 Codex Pages
  
• 5 Secrets
  
• 1 Rune
  
• 2 Doomtoys
  
• 1 Sentinel Battery
  
• 2 Secret Encounters
  
• 1 Album
  
• 1 Automap
  
• 1 Weapon mod
  
• 1 Sentinel Crystal
  
• 1 Slayer Gate Key

Start the mission and drop down off the ledge in front of you to find an extra life directly below.
Continue on and break through the green wall not far ahead and then take a left to find a codex page.
Proceed into the next small area with the locked gate and in the far right corner from where you entered will be a wall that you can break through, inside is a piece of armor which is a hidden secret.
Collect your glove for the blood punch ability and then head down in the elevator, follow the mission objective and you will collect your first rune as part of the mission.
After using the rune turn around and you will see that we now have access to a yellow bar that will allow us to reach the upper level, swing up and on the left side you will find an extra life.
Now continue down the stairway but before you drop down into the room below there is a small room at the end of the stairway, inside the room is a breakable wall, break through the wall and inside will be a doomtoy.
Now drop down into the room below and clear it of demons, then look up and above one of the archways will be a blue orb, use the yellow bars to swing up and collect it for another secret item.

Continue on with the mission until you reach outside.

Follow the mission objective outside and you will need to swing up over to a large platform with a big statue kneeling down, from that platform if you look opposite towards the direction you came from you will see a codex page next to the gate, simply jump across to collect it.
Proceed with the mission into the building with the rotating electrified walls, at the back of the room is a cube you can melee and then use to climb up to the upper level. On the upper level you will see a codex page on the opposite side, use the top of the rotating walls to get across and collect it.

Continue the mission and gain your dash ability.

After picking up the dash ability head outside towards the mission objective but before jumping across look directly down over the edge of the platform you're standing on and you will see an extra life. You can either drop down to collect it or jump across from the opposite platform.
NOTE: In this area you will have 2 items to collect. Continue the mission along the path and through the door at the end, this will take you to the throne room and sitting behind the throne will be another extra life.
 
As you leave the throne room turn right into the passage to find a codex page.
Now you can continue the mission until you reach another Hell Knight encounter back where we were before.
After the Hell Knight encounter make your way back outside, you will notice the gate is now open allowing you to collect the sentinel battery straight in front of you.
From here do not follow the mission objective as we will be heading to the first secret encounter.
NOTE: For this encounter you will be attacked by 2 Cacodemons. On the far right side from the mission portal you will see a building in the distance, located there is the secret encounter. To reach the encounter use the yellow bars to swing across, you will need to jump from the higher ground to reach the first yellow bar.

After completing the secret encounter continue the mission into the portal.

When porting to the next area you will pick up the plasma rifle. Clear the area of demons and head to the lower area and melee the cube located next to the giant mech hand, the cube will move and reveal an opening in the ground and inside will be an album to collect.
NOTE: In this area you will have 3 items to collect. After collecting the album go back to the giant mech hand and enter the mouth like entrance nearby. When inside follow it around through the purple goo to find an automap, continue around and you will need to jump across to the wall and then on to the opposite platform.
From the platform jump off and collect the extra life floating in the air, you will then need to come all the way back around to the platform and this time stay on the platform and collect the weapon mod, from there continue the mission along the path.
 

After activating the mech hand and destroying the wall you will need to go through and climb two more walls, climb up and on the top platform will be a codex page, you can't miss it.
After collecting the codex page you will need to stand on five green plates to unlock the gates ahead. Activate the plates and when you drop down into the hole and stand on the third plate look across to the outer wall lower down and you will see a breakable wall, break through and inside will be a blue orb.

Continue the mission and activate the rest of the plates, and then make your way all the way through and up to the giant mech spear.

NOTE: For this encounter you will be attacked by 5 Lost Souls. When you reach the back end of the giant mech spear, look down to the right side just behind the mech body and drop down into the gap. At the end of the path will be the secret encounter.

After the encounter go back and continue the mission along the mechs spear, the mech will create a hole in the wall using the spear. Enter the hole and proceed with the mission until you reach another mech that will this time blow a hole in the wall using a gun.

After the second mech has blown a hole in the wall enter inside and take the left path through the purple goo and there you will find a sentinel crystal.
NOTE: In this area you will have 2 items to collect and 1 secret to find. After collecting the crystal you will drop down into a hell like open area, you will also see a small cut scene showing the unstable platforms.
If you look down towards the lava on the right side you can see a codex page on the platform on the far side, drop down and use the path next to the wall to reach it.
 
From the codex location look into the lava under the rock archway and you will see a yellow bar, use the yellow bar to swing across under the archway and onto the platform in the far right corner. On the platform will be a breakable wall and inside will be a blue orb secret.
 
After collecting the blue orb head to the first unstable platform, from there over the chains you will see the lava flowing to the right side of the next unstable platform under a small rock archway. Jump over the chains and into the lava and follow it through the archway to find a secret barrel easter egg on the left side (keep to the edge of the lava to prevent damage).
Continue the mission and further up and along the rocks you will come across the slayer gate, to access the gate you will need the slayer gate key.
 
The key is located just outside of the slayer gate on a platform high above. To reach the key you will need to enter the tunnel to the left of the slayer gate. When entering the tunnel do not follow the mission towards the green lights and instead climb the rocks on either side to the top platform, from there jump across to the opposite platform which will lead back outside and allow you to jump across and collect the slayer gate key.

If you choose not to do the slayer gate during the mission then you will have to run the mission again and collect the key, the slayer gate also counts towards your exploration collectables.

NOTE: In this area you will have 2 items to collect. From the slayer gate continue the mission and you will have to make your way across a few walls, after the walls you will land on the ground/platform, from there turn around and face back towards the walls and you will see an extra life floating in the air opposite.
Go and collect the extra life then return the platform.
 
From the same platform look over to the top of the lavafall nearby and jump across, hidden away at the back tucked in the rocks will be a doomtoy.
Continue the mission and you will come to another short cut scene and meet another slayer, in this area you will not be able to shoot your guns.
After the cut scene make your way up the stairway and at the top will be a codex page that you can't miss.
In the next area you will have to make your way across several unstable platforms and fiery chains. Jump across the first set of unstable platforms to the next solid platform.
From that solid platform look to the left side of the big rock in front of you and you will see an extra life underneath one of the unstable platforms. Jump across to the large rock and then jump out and collect the extra life. That will complete all items for this mission, continue on along the platforms and kill the demons to activate fast travel and/or complete the mission.

Time to head back to the fortress of doom.

NOTE: We are back at the fortress and are able to collect a few more items and check out our home that little bit more. Keep on track with the guide and you shouldn't miss anything. Current items available:

• 1 Praetor Suit Token
  
• 1 Codex Page
  
• 1 Secret
  
• 1 Broadcast Log

This is part of the mission so it can't be missed, it will also be your first suit point.
From the main room where the mission portal is located head through the left or right doorway and down the stairway to where the super shotgun hologram is shown rotating. From the shotgun head through the largest doorway leading underneath the main room, behind the large rotating device you will find the slayers personal quarters with a codex page inside, you can't miss it.
Whilst you're in the slayers personal quarters you will see a PC with doom 1 and 2 installed on it. To play Doom 1 you will need to complete the cheat code collection (Floppy Disks) and to play Doom 2 you just need the password which is: flynntaggart
You will collect this when activating the portal for mission 3.

Time to begin mission 3

NOTE: This mission contains another slayer gate and also a few hidden items. This is a good mission and it shouldn't be too difficult to find everything. This mission contains:

• 1 Codex Page
  
• 2 Doomtoys
  
• 3 Sentinel Batteries
  
• 6 Extra Lives
  
• 5 Praetor Suit Tokens
  
• 1 Rune
  
• 4 Secrets
  
• 1 Weapon Mod
  
• 1 Automap
  
• 2 Secret Encounters
  
• 1 Sentinel Crystal
  
• 1 Cheat Code
  
• 1 Album
  
• 1 Slayer Gate Key

Begin the mission and when you spawn immediately turn around and behind you will be a codex page sitting in the corner.
Now move on and you will drop down into another area, in that area you will see a large skull hanging on the left side with a doomtoy sitting on the top.
To reach the doomtoy use the booster to get up to the wall above and make your way across to the wall with the red mines, from there climb up but do not break through the green wall and instead turn left and break the wall at the end which will allow you to jump over to the skull and collect the doomtoy. Now you can proceed through the green wall.
After going through the green wall immediately turn right and just off the edge of the map is a platform you can jump over to, break the wall and melee the mechanism inside. This will unlock the booster underneath the central platform and allow you to reach the sentinel battery in the gap high up in the rocks.
In the same area look down over the edge of the main steel platform, you will see a funny looking creature hanging from a chain and to the left of that is a mine tucked in the rocks, shoot the mine and the creature will explode into an extra life for you to collect.
Continue inside the building and after clearing the room of demons the gate at the end of the room will unlock, this is the direction of the mission and as you go through the gate you will find a praetor suit token, you can't miss it.

Move on and clear the next area.

After clearing out the demons do not proceed with the mission just yet, instead face the mission marker and look to the right side of the booster and you will see a green target. Shoot the green target and then jump across to the wall on the other side, from there you will see an extra life on a platform further along. After that go back around and continue the mission.
Proceeding with the mission make your way to the yellow door at the opposite end of the room, when you're through the door look on the right side over the edge of the map and you will see a yellow bar. Use the yellow bar to swing forward and then dash left to reach a hidden platform with another strange creature stuck in the wall, break through the wall to find another extra life behind it.

Now continue the mission until you pick up the rocket launcher.

NOTE: In this area you will have 2 items to collect. After picking up the rocket launcher you will battle it out with more demons, once the area is clear melee the mechanism in the room opposite the yellow bar and make your way upwards using the yellow bar when it raises. Almost at the top you will find a rune, collect the rune and then immediately jump across to the coffin shaped platform hanging behind it and at the back of the platform will be a hidden blue orb.
NOTE: In this area you will have 2 items to collect. Continuing the mission and further along you will need to stand on the green plate to unlock the door ahead, open the door and straight ahead will be a weapon mod for you to collect.
 
Immediately after the weapon mod continue down the passage next to you and half way down on the left side will be a breakable wall, break through and follow it around to collect another praetor suit token.

Continue the mission and then clear the outside area to proceed further.

NOTE: In this area you will have 2 items to collect. After clearing the area the bridge will drop down and the gate will open, head inside and take the left path to find the sentinel battery at the end. Now go to the opposite end and melee the mechanism to briefly activate the yellow bars, quickly use the bars to swing up to the small piece of wall and from there jump across and collect the extra life floating in the air.
Moving on to the next room simply kill all the worshipers to unlock the secret blue orb which will appear in the center of the room.
Continuing the mission into the next area, once again clear the demons and then exit the only door open and turn left instead of right to find your automap.
 

NOTE: In this area you will have 2 items to collect.
Secret Encounter
For this encounter you will be attacked by 1 cacodemon, 1 revenant, 2 shielded soldiers, 2 cueballs. From the automap follow the mission objective and unlock the gates using the skull pedestal. Once the gates are open you will see the sentinel crystal directly in front of you in the central structure and on the left side will be the secret encounter.
After the secret encounter move into the next room and use the left side mechanism to take you down to the level below. On the level below follow the passage all the way around and just past the mission objective further on will be a praetor suit token.
After collecting the praetor suit token continue the mission and activate the yellow bar to reach the wall on the other side of the room, from the wall jump across to the left side mechanism and it will take you up a level.
When you reach the upper level head into the other mechanism on the opposite side and it will take you further up, from there follow it around to find the sentinel battery in the back room.

Continue the mission until you gain your super shotgun.

NOTE: In this area you will have 2 items to collect. After you have gained your super shotgun you will enter a room where you will need to break the chains on each block to reveal different demons. Clear the room of demons and once clear you will find a cheat code hiding up in the top of the central structure, use one of the yellow bars to swing up, dash around and collect it.
 
Now follow the mission marker and drop down into the hole in the central structure. Half way along the passage you will see a breakable vent on the right side, break through it to gain another doomtoy.
Continue into the next room and once you have activated the skull pedestal you can be boosted onto the central rotating block. From the central block jump onto the platform on the opposite side of the mission marker and on there you will find a praetor suit token.

Proceed with the mission and climb the tube shape walls to the very top.

Secret Encounter:
For this encounter you will be attacked by 2 whiplash, 1 mancubus, 2 mecha zombies. After you have finished climbing the walls and you're at the top, head into the nearby tunnel and inside take a right into a small room. Inside the room you will find a breakable wall and behind it will be the secret encounter.
Continuing after the secret encounter you will need to shoot the green target through the spikes and then drop down and dash to the wall on the other side. Climb the wall and half way up opposite you will be an extra life. After that make your way to the next room.
NOTE: In this area you will have 2 items to collect. As you enter the next room look to the right at the spiked crusher and when it hits the ground stand on the top of it to reach the blue orb in the gap above.
 
This time from where you entered the room head to the the crusher on the far left side, when it hits the ground walk through to the left side and further along will be an album. Now continue the mission until you're lifted up to the outside.
When you have been lifted up and back outside head to the edge of the map on the far side and look down to the right, you will see an opening in the rocks that you can jump across to. Inside the opening will be a strange looking creature, use the skull pedestal on the right side of the room to unlock the extra life and a booster outside to get back up.

Continue the mission until you reach the slayer gate.

Now you are at the slayer gate you will need the key. To access the key you will need to head to the right side of the large statue, from there look down over edge of the platform and on the right side will be a wall you can climb. Drop down onto the wall and under the platform will be yellow bars you can use to swing across underneath, make your way underneath and at the end you will find the slayer gate key.
Proceed with the mission into the next area and before you make your way outside follow the right passage to collect another praetor suit token.
After the praetor suit token drop down outside and destroy the demons. Once the area has been cleared look to the left of where you entered the area and you will see a door with a breakable chain, break the chain to find a secret powerup inside. That will be the last item to collect for this mission.

Another mission complete, but this time we will go straight to the next mission.

NOTE: With this mission there is a good amount of platforming, this is also the mission that gets you the achievement for killing 3 doom hunters. Overall it's not too bad a mission and the items are not too difficult to find, but just be careful not to end the mission too early by dropping down the hole after killing the first doom hunter. This mission contains:

• 1 Weapon Mod
  
• 4 Praetor Suit Tokens
  
• 3 Extra Lives
  
• 2 Sentinel Batteries
  
• 3 Codex Pages
  
• 1 Automap
  
• 2 Doomtoys
  
• 1 Rune
  
• 1 Album
  
• 1 Cheat Code
  
• 1 Sentinel Crystal

NOTE: In this area you will have 3 items to collect. Start the mission on the moving platform and when you reach the building climb up to the top and make your way over to the platform on opposite side of the room, on the platform to the left of the large green door will be a weapon mod.
 
From the weapon mod look towards the centre of the room and you will see a yellow bar moving up and down, wait for the bar to lower and then use it to swing across onto the wall located on the opposite side. Climb onto the top of the wall and from there look towards the back of the room and on the right side you will see a praetor suit token on a platform, simply jump across and double dash to collect it.
Now go back to the center of the room and above the yellow bar on a small platform is an extra life, wait for the platform to lower and then jump across and collect it.
Make your way into the next room and clear out the demons, once clear look in the center of the room and underneath the central platform with the arches and there will be a breakable shaft, break through and follow it around to find a sentinel battery.
Continue the mission up the stairway into a small room and do not enter the green portal, instead look opposite the portal and you will find a codex page. Now you can enter the portal.
After entering the portal you will come to a room with a yellow doom hunter hologram rotating in front of you, on the right side of the hologram you will find an automap.

From here continue the mission and make your way across several platforms/walls until you reach the molten metal area further up, it will be full of zombies, a couple of revenants and one carcass.

NOTE: In this area you will have 3 items to collect. In the molten metal area head to the very back and climb onto the platform that moves up and down. Facing the direction you came from look slightly above and you will see a doomtoy located in the tube not too far in front of you. Jump across when the platform you're on rises.
 
Immediately after the doomtoy drop down across to the platform towards the mission marker and in the next room you will find a codex page on the right side and a rune on the far left side.

Now continue the mission all the way until you reach a small cut scene where the top half of the doom hunter is being taken out of the coffin shaped stone box.

NOTE: In this area you will have 3 items to collect. After the cut scene head into the next room and climb onto the platform at the back, from there climb up onto the nearby wall and stand on top of it. If you look up at the central pillar you can see a small hatch that you can climb through, to reach the hatch you will need to jump across to the wall and climb higher up then from there jump out and dash around to the wall below the hatch.
Drop down inside to collect the Album and from here you can move on to the next.
Now jump across to the room opposite and activate the skull pedestal, then immediately jump across again to the next wall and follow it around anti-clockwise to reach the top of the structure.
At the top of the structure will be a Floppy Disk.
 
From the top of the structure drop down the hole and inside will be a praetor token, after that use the nearby portal and continue the mission.

Now make your way across a few more platforms and walls until you reach the location of the red key card.

NOTE: In this area you will have 3 items to collect. When you reach the large structure the red key card will be inside, but before you enter head to the back of the platform and you will find a sentinel crystal.
 
From the sentinel crystal head to the opposite side of the platform underneath the structure and you will find an extra life.
 
Now go back to the sentinel crystal and from there head inside the building, climb the wall and on the right side just in front will be a sentinel battery. You will also find the red key card on the left side further around, from there you can jump back across to unlock the main door.
 

After entering the red door make your way down the slope and you will head back up via the stairways on either side, when you reach the top take the right side passage and in the room will be a praetor suit token located in the shaft above. Climb the crates on the left side to reach the shaft.

Continue the mission until you reach another small cut scene.

After the cut scene you will reach another outdoor area where you will need to swing across and break into the shaft lower down. Before you jump look straight across and you can see a extra life through the window of the machine. Make the jump and once inside climb up and and walk around the heated machine to collect the extra life.
To continue the mission there is another platform above where you entered the machine, climb up to proceed.
From this point you will need to jump across more platforms up to the building that has the red electrified wall surrounding it. When you reach the building follow the ledge all the way around until you come to a praetor suit token, just be careful of demons along the way.
To proceed with the mission climb the nearby wall and shoot the green target above the platform in the distance which will allow you to jump across and continue.
NOTE: In this area you will have 2 items to collect.
WARNING: After killing the first doom hunter, dropping down the hole will start a new encounter with two other doom hunters and automatically end the mission when they are both dead. Once you have jumped across from the electrified building make your way through and again jump over to the next area. When entering the doorway you will see a codex page at the bottom of the slope, collect the codex page and then turn around and look up above and you will see a green target located in the ceiling, shoot the green target and it will lower the slope in front of you and give you access to the doomtoy inside.

That completes the items for this mission, so go ahead and have fun killing those damn doom hunters to finish the mission.

NOTE: You now have access to another secret at the fortress and two more items. You can choose any items you want to collect but for the sake of this guide it's best to keep following along, i would also advise not wasting your sentinel batteries on praetor suit tokens. Save at least 4 sentinel batteries for the end of the campaign so you can collect the last two slayer outfits. Current items to collect:

• 1 Cheat Code
  
• 2 Sentinel Crystals

From the main room head towards the doom slayers personal quarters located underneath, but before you reach his room take the door on the right side that leads outside. Follow the path to the end and use 2 sentinel batteries to unlock the door and gain the original praetor suit.
Inside the same room as the suit will be a hole in the wall, drop out of the hole and jump/dash onto a hidden platform underneath that contains a cheat code.
From the main room head to the back of the fortress and on the level below the Demaykr will be two rooms with sentinel crystals inside, unlock them both using the sentinel batteries to collect them.

Continue to mission 5.

NOTE: This mission is a bit of a maze but i will guide you as best i can. We will also need to bypass a few items and come back for them when we gain access, so don't worry about missing anything. And as there is so much to collect i have also had to split this mission guide into 3 parts, but this should be the only 3 part mission This mission contains:

• 3 Codex Pages
  
• 3 Doomtoys
  
• 2 Weapon Mods
  
• 4 Extra Lives
  
• 1 Secret
  
• 5 Praetor Suit Tokens
  
• 2 Secret Encounters
  
• 2 Runes
  
• 1 Cheat Code
  
• 1 Sentinel Crystal
  
• 3 Sentinel Batteries
  
• 1 Automap
  
• 2 Albums
  
• 1 Slayer Gate Key

Start the mission and make your way outside, opposite you under the platform will be a codex page, collect it and proceed through the green wall.
NOTE: In this area you will have 3 items to collect. After breaking through the green wall into the next area clear the demons out and on the opposite side to where you entered the area will be a platform high up on the building. Use the two nearby yellow bars to swing up and collect the doomtoy on the platform.
 
Continue into the building where the mission marker shows and straight in front of you as you enter will be a codex page.
 
After the codex page climb the walls nearby but take the opening at the top on the right side, don't follow the mission marker. Once you're up follow it around and inside you will find a weapon mod.
NOTE: In this area you will have 3 items to collect. Continue the mission and in the next big circular room the mission will direct you into the opening above, do not swing up just yet but look to the right side of the upper level from where you entered the room and you will find a breakable wall, break through and outside you will be able to reach the extra life that we passed earlier.
 
Once you collect the extra life the structure will drop down and next to it will be an opening with a health pack inside, go inside and you will collect another secret.
 
From here head across to the pillars opposite to find another opening with a praetor suit token inside.
Make your way back to the big circular room and now swing up to the opening above, once you're up immediately turn around to find another opening and jump across, further inside will be a doomtoy.
NOTE: In this area you will have 2 items to collect.
Secret Encounter:
For this encounter you will be attacked by 2 mancubus and 2 mecha zombies. After the doomtoy proceed and you will drop down into another room and activate a buff totem. Clear some of the demons and four portals will appear in the center of the room. If you stand next to the buff totem and face the portals take the nearest portal on the right side, this will bring you to the buff totem allowing you to destroy it right away and after that the first portal will close.
 
From the buff totem location, face the portals once again and this time take the nearest portal on the left, this will bring you to an armor piece and close the second portal once we exit the small enclosure.
 
Now go back to the buff totem location, face the portals and take the furthest portal on the left, this will bring you to the praetor suit token and this time close the third portal.
 
Proceed through the fourth portal and this will take you to the location of the secret encounter, but you will notice it is still locked. To unlock the secret encounter head towards the center of the room and allow the fourth portal to close and then go back. Do not enter the new portal first.
After the secret encounter you can now enter the new portal that appeared in the center. Pick up the yellow key and proceed through to the next yellow door and instead of turning left at the end of the passage look to the right side and use the booster to collect a rune on the platform above.
NOTE: In this area you will have 2 items to collect. After collecting the rune you will come out into a big open area full of lava and demons.
In the center of the area lower down will be a blue orb floating just over a small rock. This is not an item or secret you need to collect but as you have been collecting other blue orbs you can collect this too.
 
From the blue orb climb back up on the left side of the area and if you look over towards the mission marker you will see a breakable wall on the outside of the structure, jump across and break through and you will find the cheat code inside.
Continue the mission and when you have placed the yellow key into the eye it will unlock the area inside the structure just below, enter the area and you will see an extra life floating in the air on the right side. To reach the extra life use the yellow bar located on the central pillar to swing up and collect it.
 

After collecting the extra life enter the shaft and drop down into the lower level, follow it around to find a sentinel crystal and then proceed into the next shaft.
After dropping down from the second shaft continue the mission until you come across the chaingun that is locked away in a small enclosure. As you face the enclosure on the right side in the corner is a codex page.
Make your way into the next room and pick up the rad suit on the opposite side, from there make your way past the fiery chains and into the room with the rotating column. Don't use the yellow bars on the column just yet and instead take the lower passage and follow it all the way around to find a sentinel battery.
After collecting the sentinel battery go back to the room with the rotating column and use the yellow bars to swing up and break through the wall. Once through make your way around and you will see a blue orb sitting on the far side in the top circular opening, jump and dash across to collect it.
NOTE: In this area you will have 2 items to collect.
Secret Encounter:
For this encounter you will be attacked by 1 mancubus, 1 carcass and 8 zombies. After the blue orb head into the next room and don't drop down, instead jump over to the top of the structure and tucked away in the back will be the secret encounter for you to complete.
Just be aware that for the encounter the mancubus will spawn right in front of you but the rest of the demons will spawn in the toxic sludge below.
 
Once you have completed the secret encounter, go back to the top of the structure and face where the secret encounter was located, look down to the right side and drop down into the passage and you will find a doomtoy.
After collecting the doomtoy once again go back to the top of the structure and this time face away from the secret encounter location and look over to the right side. Jump across and onto the top of the toxic waterfall and further along will be an extra life.

Now go back a final time to the top of the structure and climb the walls on either side to continue the mission and pick up the red key.

When you have picked up the red key immediately enter the left passage into the toxic sludge and at the very end you will find a praetor suit token.

Continue the mission until you have to leave the heart chamber and don't forget to pick up your chaingun on the way through.

When exiting the heart chamber immediately turn left and into the next room to find an automap sitting near the window.
In the next room you will have to activate the the skull pedestal hidden at the back, once activated do not enter the portal and instead when facing the portal take the right passage and follow it to the end and you will find a weapon mod. Now you can go back and enter the portal.
After entering the portal it will bring you outside to more lava and fiery chains. You will have to destroy the buff totem by making your way around to the far left side and then heading up, but do not take the booster up and instead drop down the hole inside the cave to collect an extra life on the way down. Be careful not to drop too far otherwise you will die/respawn.

Once you have destroyed the buff totem drop back down to where you entered the area from the portal and on the opposite side will be a wall you can climb, climb up and at the top you will see a large cube. You will need to melee the cube to progress further but before you do you can find a praetor suit token to the left of the cube, you can't miss it.
NOTE: In this area you will have 3 items to collect. From the cube location climb up and make your way across the platforms through the fiery chains and once you reach the building with the hologram you will see a sentinel battery on the left side of the room.
 
After the sentinel battery do not break through the green wall just yet, instead look out of the window towards where the buff totem was located and you should see another item sitting in the building on the opposite side. To reach the item you will need to jump and swing across using the yellow bar that is connected to the rotating skulls in front of you, just time it right.
 
Now go back up to the building we just jumped from and break through the green wall to find a rune inside the next room.
 

After collecting the rune continue through the next green wall and you will eventually come to another toxic sludge area that requires more platforming.
Make your way across the walls and in the top left corner will be a praetor suit token on the highest platform, you might not see it until you reach the fourth wall but you won't miss it anyway.
NOTE: In this area you will have 3 items to collect. Continue all the way through until you're back outside and directly opposite you will be a blue door, go through the blue door and you will find an album inside.
Immediately after collecting the album continue through and you will be back in the starting area. At the bottom of the central structure are more blue doors, head inside and use the booster to launch you up and reach the wall high up on the building nearby.
Once you're up go through another blue door and follow it all the way through to find the slayer key and a sentinel battery, just be careful of the spectre hiding inside.
After collecting both you can now jump out and complete the slayer gate and mission.

Another mission complete, lets head back to the fortress of doom.

NOTE: A brief stop at the fortress and again it is up to you what you collect, just remember to focus all other items before collecting praetor suit tokens or just keep following this guide.
As we only have 4 sentinel batteries this time we can only collect two items. Current items to collect:

• 2 Weapon Mods
  
• 1 Arc Broadcast Log

At the back of the fortress on the same level as the Demaykr you will find the two weapon mods in the furthest left and right rooms.
You will collect this when activating the portal to the next mission.

Start mission 6.

NOTE: This mission has a lot of items to collect just like the previous mission but with added purple goo. Most of the items are pretty straight forward to find with a lot of them close together so navigating shouldn't be much of a problem with this one. This mission contains:

• 3 Doomtoys
  
• 5 Praetor Suit Tokens
  
• 1 Slayer Gate Key
  
• 3 Sentinel Batteries
  
• 1 Automap
  
• 2 Weapon Mods
  
• 1 Cheat Code
  
• 4 Data Logs
  
• 5 Codex Pages
  
• 1 Sentinel Crystal
  
• 3 Extra Lives
  
• 2 Secret Encounters
  
• 2 Runes
  
• 2 Albums

Begin the mission and drop down into the elevator shaft. When you hit the bottom follow it around to the dead end and in the right side corner will be a small room, inside the room behind the pillar will be a doomtoy.

Continue the mission through the building until you reach the ground floor, you will know when you are there because you will see the purple goo and demons fighting outside of the window.

When you reach the ground floor the mission marker will direct you to climb up into the hole located in the ceiling, but instead go to the opposite end of the room and at the back will be a breakable glass door with a praetor suit token inside.

Now make your way outside and kill all demons, you will then be directed into the opposite building and when you're inside make your way up through to the slayer gate, from there you can collect more items.

NOTE: In this area you will have 5 items to collect. Stand outside of the slayer gate and next to the gate is the automap, you can't miss it.
 
Again standing next to the slayer gate look out across the broken walkway nearby. On the opposite side in the small opening will be a sentinel battery and a doomtoy, jump across and you will see them on your left and right side.
 
Now go back to the slayer gate and look out across the broken walkway, but this time on the right side wall you can see a wall you're able to climb, use it to jump across and collect the slayer gate key on the opposite side.
 
After collecting the slayer gate key drop down into the hatch behind it, but do not exit through the window and instead look towards the broken walkway and slightly left to see a weapon mod. Collect the weapon mod and then continue the mission out of the window.
NOTE: In this area you will have 3 items to collect. After the slayer gate exit the window and use the yellow bar to swing across to the opposite building, directly in front of you will be a hole in the ground with a cheat code sitting inside.
 
From there move up the stairway and at the top on the right will be a data log, press it and collect.
 
Continue further around to the right and you will come to a breakable wall, break through and inside will be a weapon mod which should be the final weapon mod in the game, collect it and proceed with the mission.
NOTE: In this area you will have 2 items to collect. Continuing the mission you will come to a huge booster that will lift you up high and allow you to dash across to the opposite building, after that you will need to make a big leap across to another building. Once you land immediately turn to the left and in the corner just over the rubble you will find a breakable wall, break through and at the very top of the stairway will be a codex page.
 
From the codex page head back down the stairway and into the hole in the wall, just around the corner on the right side will be a sentinel crystal. Now you can continue the mission through the green wall and start swinging.
NOTE: In this area you will have 2 items to collect. After the first set of bars you will reach a platform with a large cube, melee the back of the cube and use it to reach the next small room further up. When you reach the room there will be another data log and a breakable wall with an extra life behind it.

Continue swinging further up using the yellow bars until you're back inside at the top of the building.

When you reach the top of the building you will be directed to jump across another large gap with the front of an aircraft on the opposite side. Before you jump look to the left side of the opening where you are to find a praetor suit token.
NOTE: In this area you will have 3 items to collect.
Secret Encounter:
For this encounter you will be attacked by 1 cacodemon, 1 pain elemental, 1 arachnotron.

After jumping across the large gap make your way through the front of the aircraft and into the next room with the large hole in front of you. Clear the room and proceed up the stairway to the next level.

When you reach the next level take a left and follow it around, you will see the secret encounter along with a praetor suit token on the other side of the large hole. On the nearside straight ahead of you will be a codex page hiding behind the pillar, collect the page and from there you can jump across for the secret encounter and praetor suit token.
 

After the secret encounter make your way up to the next level once more and at the top of the stairway take another left through the opening and inside will be a doomtoy.
NOTE: In this area you will have 2 items to collect. Continue the mission and jump across into the next building, as you walk through demons will jump out on the right side and give you access to a small room, inside the room will be an extra life.
 
Make your way further into the building and drop down into the hole. In front of you as you land will be a rune. Now continue the mission.
After collecting the rune you will be dropped down into a large room, this will be a good demon fight. Clear the room and as you face the kitchen area at the back there will be a codex page tucked away behind the desk in the right side corner.

Continue now until you fire the first gun turret.

After firing the first gun turret head down in the lift and at the end of the passage after killing the demons is a small room with a sentinel battery inside, collect it and move on.
NOTE: In this area you will have 2 items to collect. After entering the elevator it will take you down to the lower level. At the lower level walk forward and the floor should collapse, from there climb up and hidden away on the left side at the very back behind the machinery will be a codex page.
From the codex page proceed through opening in the wall and immediately on your right will be a praetor suit token.
As you walk through the passage the floor will collapse once again, drop down and on your left side will be a rune, you can't miss it.

Now continue the mission until you reach the purple goo that slows you down.

After a big battle you will drop down into the sewers full of purple goo, continue on and you will drop down again into a more open area full of purple goo.
You will see a large cube on the right side, melee it twice to move it and then use it to reach the yellow bar and swing across to the sentinel battery on the other side of the fence sitting on a platform.
I also noticed a crocodile under the platform that the battery sits on that quickly disappeared when i got close, weird.
NOTE: In this area you will have 4 items to collect.
Secret Encounter:
For this encounter you will be attacked by 1 mancubus, 3 prowlers. Make your way into the elevator and when you reach the lower level continue down the passage through the electric sparks, as you turn the first corner you will notice a locked door on your left side. To unlock the door follow the passage further along and in the small room at the end on the left side will be a yellow button you can activate. Activate the button to unlock the door and then go back to the door which should now be green, inside will be a codex page for you to collect.
From the codex page climb up to the nearby platform above with the green lights to find an extra life behind the large piece of machinery.
 
After the extra life drop down to the lower area and on the far left side behind a couple of crates you will find a secret album and on the far right side you will find the secret encounter.

Continue the mission past the next gun turret until you reach the indoor car park.

NOTE: In this area you will have 4 items to collect. Once you reach the car park you will have a big battle with a few demons, after clearing the area stand near to where you entered and look slightly right towards the center of the room and you will find a blue orb.
 
Now again go back to where you entered and this time on the left side you will see a small room with a data log and an album inside. Now move to the lower level car park.
As you head down to the lower car park a mancubus will jump out from the wall opposite you and reveal a praetor suit token, collect the token after clearing the area and then head back outside following the mission.
When you're back outside make your way to the ARC building. As you enter the ARC building you will see a data log on the left side, press and collect. This will complete all items for this mission.

Now have fun with the marauder and finish the mission (The ballista works a treat btw).

NOTE: Once again a brief stop at the fortress, only two items to collect here which includes the broadcast log. You can if you wish collect one of the slayer outfits instead of the token because you will not gain enough sentinel batteries to collect everything in the fortress at the end of the campaign. I only chose the token for the gameplay benefit. Current items to collect:

• 1 Praetor Suit Token
  or
  
• 1 Slayer Outfit
• 1 Arc Broadcast Log

You should know your way around here by now so head to the Demaykr and unlock one of the doors on either side for your praetor suit token.
You will collect this when activating the portal for the next mission.

Mission 7 awaits.

NOTE: We have a lot of platforming on this mission and a few items that you could miss if you're not careful, but i have tried to guide you as best i can without overcomplicating things which i hope works out. Overall this is a pretty good mission with plenty to collect whilst also finding the last of your runes here. This mission contains:

• 2 Runes
  
• 6 Extra Lives
  
• 3 Sentinel Batteries
  
• 1 Automap
  
• 5 Praetor Suit Tokens
  
• 2 Codex Pages
  
• 2 Secret Encounters
  
• 3 Doomtoys
  
• 1 Cheat Code
  
• 2 Albums
  
• 1 Sentinel Crystal
  
• 1 Slayer Gate Key

Start the mission and make your way through until you head down in the elevator. On the lower level when you exit the elevator you will encounter a baron of hell, kill the demon and then make your way through into the next room and find a rune straight in front of you as you go through the door, you can't miss it.
From the rune head outside under the BFG10K and on the left side floating in the air just off the edge of the map will be an extra life, collect it and then move up into the next area.
In the next area you will battle it out with a doom hunter, once it's been dealt with follow the mission marker and drop down into the hole, when you drop down face away from the mission marker and you will see a sentinel battery on the far platform, hop over to collect it and then continue into the machine.
NOTE: In this area you will have 3 items to collect. After entering the machine you will reach a room that is fairly green with 4 piston type structures moving up and down and a green fan spinning on the back wall. In front of the fan is an automap, collect the map and then climb up into each piston to reach the very top.
 
At the top do not follow the mission direction into the shaft just yet and instead look on the opposite side and you will find a praetor suit token on the platform lower down.
 
Now follow the mission marker through the shaft and immediately on your left side will be a codex page, collect it and then move on from here.
Continue the mission until you head back outside and enter the portal on the right side, this will take you to a new area. In the new area you will need to do some platforming and when you reach the other side enter another building and take the right passage to find an extra life. Do not worry about the secret behind the locked door as we will be coming back for that later.
NOTE: In this area you will have 2 items to collect.
Secret Encounter:
For this encounter you will be attacked by 1 revenant, 1 spectre, 1 imp, 2 gargoyles. After picking up the extra life you will once again head back outside and have another buff totem to destroy, destroy the totem and demons and then follow the mission marker into the hole.
As soon as you drop down into the hole look to the left side and you will see a breakable wall, break through and lower down on the right side is an opening that you can drop and dash into.
The opening is a little hard to see but it is there and once inside you will find a praetor suit token and the secret encounter.
After the secret encounter make your way into another elevator. When you reach the top follow it around to the right side and you will find a doomtoy at the end. This was the item we seen earlier when collecting the extra life.
Now continue the mission and activate the computer terminal, when the doors unlock go through and you will see a rune in front of you just past the hologram, you can't miss it. This should be your final rune for the campaign.
After being fired through the cannon into the next area take the right side passage down the stairway, follow it around and then take the next right and use the booster to jump up a level. On the edge of the hole that you jumped through will be a cheat code.
NOTE: In this area you will have 3 items to collect. After the cheat code make your way into the next room and then take the door on the left side, inside will be a set of crates you can climb to reach the upper platform where a praetor suit token is situated.
Now from the praetor suit token jump across to the platform just above the blue booster. From the top of the blue booster turn around and face the direction you just jumped from, you will see a album hidden in the shaft out in front of you up above. Use the yellow bar to swing up and collect it.
Immediately from the shaft jump back towards the booster but this time using the yellow bars to break through the wall on the opposite side and inside the small room will be an extra life.

To continue the mission drop down the large hole that we have been jumping over, it looks like you might die if you fall but it actually takes you back outside.

NOTE: In this area you will have 2 items to collect.
Secret Encounter:
For this encounter you will be attacked by 1 whiplash, 4 imps, 1 prowler, 1 cacodemon. After dropping down into the large hole enter the building on the left side. When inside break through the vent up ahead and enter the portal which will bring you to the secret encounter.
 
After completing the secret encounter use the nearby booster to jump up to the level above and inside at the back of the room will be a doomtoy.

From the doomtoy continue the mission and make your way across more platforms to the next small battle area. You will need to kill everything in the area to unlock the door.

NOTE: In this area you will have 5 items to collect. After going through the door and then through the building you will come to more platforming.
Starting from the top look across to the small structure ahead with the rotating transmitters, on the top of that structure will be an extra life.
You will need to use the nearby booster and land on the very top next to the extra life otherwise there is no access from lower down.
 
From the transmitter look further ahead on the smaller platforms and you will see a praetor suit token on the far side, use the nearby platform to reach it or if you drop down use the walls to reach the nearby platform and from there you will be able to jump across.
 
Now from the praetor suit token drop down onto the large platform with the four electricity pins. From there make your way to the next platform using the walls underneath and as you jump from wall to wall you will see an extra life that you can collect on your way back up.
 
When you're at the top of the platform you will notice a sentinel battery on the ledge above you, to reach it use the booster to jump across to the opposite side higher up and then jump back across using the small platforms and collect the sentinel battery.
 
Now from the sentinel battery use the same booster to continue the mission and jump back across. Once across enter the nearby building and inside will be a sentinel crystal for you. To proceed with the mission from there you will need to exit the building and turn left and then jump across the opening.
NOTE: In this area you will have 2 items to collect. Once you have entered the building you will see the slayer gate key directly in front of you up above, to reach it head into the room on the left side and activate the yellow switch next to the computer. Once activated return to the room with the slayer gate key and at the back of the room on the left side will be a new platform you can stand on to reach the top right vent and break through, go inside to collect the slayer gate key.
 
After collecting the slayer gate key exit out of the vent and go back to where we just entered it but this time enter the left vent to find an album inside. Now you can complete the slayer gate or just continue the mission.
Continue the mission and drop down into the hole and as soon as you land you will see a breakable vent on the left, break through it and follow it around to find a doomtoy surrounded by a few zombies.

Continue the mission and port into the next area

NOTE: In this area you will have 3 items to collect. Immediately in the new area drop down from the rocks in front and next to you will be a sentinel battery, you can't miss it.
 
Straight after the sentinel battery drop down again and on the right side next to the flames is another codex page.
 
From the codex page move on through the passage but do not break through the green wall and instead turn left, at the end of the path will be a praetor suit token. Now continue and break through the green wall.
After breaking through the green wall you will need to destroy some demons including a doom hunter. Clear the area and in the center of the area will be an extra life floating up high, use the yellow bars to swing up and collect it. That should be the final item for this mission.

Time to head to sentinel prime!

NOTE: This is a quick and easy mission and contains only a boss fight. You will find mostly codex pages throughout this mission and nothing is really hidden away so you could easily find everything without even using the guide.
You can also use cheat codes on this mission and then repeat it over and over to gain a slayer level each time you complete it, you just won't gain exp by doing it. This mission contains:

• 9 Codex Pages
  
• 2 Extra Lives
  
• 1 Automap
  
• 1 Praetor Suit Token

 
NOTE: In this area you will have 3 items to collect. Start the mission and follow the path along and you will come to your first codex page, you can't miss it.
 
Continue on and after activating the skull pedestal you will head down on the lift and a short cut scene will appear, immediately after the cut scene you will see a codex page straight in front of you.
 
Now continue through the room and just before you enter the next room there will be another codex page in the passage.
NOTE: In this area you will have 3 items to collect. Proceed with the mission and you will pass a hologram next to a large opening in the right side wall. In the next room you will see a codex page behind a gate in front of you, ignore that and instead climb the platform on your left side and use it to jump up to the opening high up on the opposite side, follow it around to find a codex page and also the skull pedestal.
 
Now from the skull pedestal look out to the opening on the opposite side, jump across and inside will be an extra life.
 
After the extra life go back to where you entered the room and now you can collect the codex page behind the gate, you can reach it by taking the left side path. 
NOTE I: In this area you will have 4 items to collect. You will next come to a large room and a hologram will appear on the stairway in front of you, ignore the hologram and on the right side right next to you will be the automap.
And on the right side of the stairway in the far room will be a codex page, you should be able to see it from the automap.
 
Once you have both items head up the main stairway and at the top turn right and follow it all the way around, when you reach the opening jump across to the opening on the opposite side to find a praetor suit token and an extra life.
NOTE I: In this area you will have 3 items to collect. Continue the mission into the next area where the lift is located and just before you reach the skull pedestal you will find a codex page on the left side.
 
From there go and activate the skull pedestal and the lift will take you up, when you reach the top turn around and behind you will be a codex page.
 
Now make your way to the end room near the boss area and on the right side of the room will be the last codex page and the final item for this mission.

Now destroy the boss, complete the mission and then we can get back to the fortress of doom

NOTE: A new item is available for you to collect and it will be the last of the hidden items. I have also added two praetor suit tokens for you to collect but again you might be best to collect the last two slayer outfits if you haven't already. Beyond this point you will only gain 4 more sentinel batteries. Current items to collect:

• 2 Praetor Suit Tokens
  or
  
• 2 Slayer Outfits

• 1 Cheat Code

• 1 Arc Broadcast Log

 
When entering the fortress of doom you will have demons to kill, clear them up and get it back online.
Once you get things up and running, from the main room go straight through to the room that contains the crucible and you will see a cheat code hidden on the platform above as you enter.
To reach it shoot the red marker on the top right central window and a red booster will appear that will allow you to jump up and collect the cheat code.
NOTE: In this area you will have 2 items to collect. Make your way underneath the main room 2 levels down and use the sentinel batteries on the two doors with praetor suit tokens behind them located each side of the giant mech.

If you don't want the praetor suit tokens head outside on the left side of the fortress to collect another slayer outfit and one in the room opposite the main room at the top.

You will collect this when activating the portal for the next mission..

NOTE: This mission has a few hidden items including an achievement for collecting and completing everything. One hidden item can be difficult to reach so you might need to use the fast travel a few times at the end of the mission which i will explain later. This is another mission that can also be difficult to navigate so i will do my best to guide you, and don't forget to complete the challenges if you want the achievement. This mission contains:

• 7 Codex Pages
  
• 3 Sentinel Batteries
  
• 2 Albums
  
• 5 Praetor Suit Tokens
  
• 2 Secret Encounters
  
• 2 Mastery Tokens
  
• 1 Automap
  
• 3 Doomtoys
  
• 3 Extra Lives
  
• 1 Slayer Gate Key
  
• 1 Cheat Code
  
• 1 Sentinel Crystal

NOTE: In this area you will have 2 items to collect. Start the mission and after jumping over to the first large platform you will find a codex page on the left side. Immediately after the codex page go to the edge of the platform nearby and drop down onto the lower part to find a breakable wall, break through and inside will be a sentinel battery, collect it and move on to fight a marauder further down.
After the marauder fight continue on and you will come to a large gap, jump and swing across the large gap using the yellow bar and when you land on the other side turn around and under the platform you just jumped from will be another small platform. Use the yellow bar again to swing back across and underneath to collect the album located there.
Now swing back using the yellow bar for a third time and continue the mission by climbing the wall on the left side of the door.
After climbing the wall up to the next platform you will meet a mancubus, kill it and turn left through the door to find a praetor suit token.
NOTE: In this area you will have 4 items to collect.
Secret Encounter:
For this encounter you will be attacked by 1 zombie, 1 cacodemon, 1 doom hunter, 1 pain elemental. After collecting the praetor suit token continue on and drop down into the hole. When you come out into the large open area, clear it of demons and on the left side as you entered the area there is a breakable wall and behind it is the secret encounter. This one can be a little difficult to complete.
 
As you face the secret encounter there is a small nook on the left with a green button inside, press it and it will give you access to the mastery token next door. To guide you better the mastery token will be on your left side as you entered the area.
Now again stand where you entered the area and this time climb to the upper platform on the left side and turn left again to find the automap just inside.
This is where things start getting tricky to navigate. As you entered the area you will see the stairway on your right side, at the top of the stairway is a room on the left side that contains a steel block on a chain that you need to break to access the sentinel battery in the room below.
 
To unlock the room with the steel block then stand where you entered the area and then head to the far right corner. You will see a statue kneeling down just to the left of the barrels and behind it will be a green button, press the button and it will unlock the gate and allow access to the steel block.
 
So now you have access go back to the steel block. Climb the wall and break the chain and then drop down into the room below to collect your sentinel battery.
NOTE: In this area you will have 3 items to collect. Proceed with the mission through the water and when exiting the water on the other side you will find a praetor suit token just behind you as you climb out.
 
Move into the next area and straight in front of you at the top of the steps will be a codex page.
 
After collecting the codex page look to the left side of the steps at the kneeling statue tucked away in the alcove, break the statue to find another green button hidden behind it. Press the button and then stand on the platform that has activated in the center of the main stairway.
 
Standing on the platform will unlock the gate situated on the opposite side next to where we entered the area and inside will be a doomtoy.
NOTE : In this area you will have 2 items to collect. Proceed through the door and after the small cut scene look down into the hole ahead and you will see an extra life, jump down to collect it.
 
On the right side of the hole head towards the mission marker and you will come across another codex page, you can't miss it.

Proceed with the mission outside and take the lift down into the sewer. When in the sewer you will come across the slayer gate, ignore it for now and drain the water in the next area.

After draining the water follow the path through the sewer and take a left just before the exit and at the top on the left side will be the slayer key.
NOTE: In this area you will have 2 items to collect.
Secret Encounter:
For this encounter you will be attacked by 2 mecha zombies, 1 marauder. After completing the slayer gate make your way out of the sewer and into the next room, as you enter take the stairway on the far right corner and at the top of the stairway on the left side will be a breakable wall. Head through the wall and inside you will find the secret encounter and a cheat code.
NOTE: In this area you will have 4 items to collect. Continue the mission and not too far ahead you will need to climb more walls, when you reach the top look behind you and you will find a codex page and a sentinel battery.
 
From there climb up the large demon to reach the crucible which will initiate a small cut scene, after the cut scene look down towards the demons legs and on the right side you will see a praetor suit token and a breakable wall with a doomtoy inside.
Proceed with the mission upwards and after the marauder encounter enter the next building and make your way to the top, on the left side just past the large opening will be an extra life. From there jump across to the next building.
NOTE: In this area you will have 3 items to collect. After another small encounter once again jump across to the next building by dashing and breaking through the wall, then follow it around and use the lift to take you up. At the top you will have another fight on your hands, so kill the demons and then follow the platform all the way around and sitting at the back will be a praetor suit token.
 
Now go back to where you stepped off the lift and look down over the edge of the building facing in the direction of the broken bridge opposite. Below is a platform that you can drop down onto, drop down and inside you will find a sentinel crystal and a codex page.
Now you can jump across to the other side of the broken bridge. Once on the other side continue along the path towards the mission objective and before you reach the doors you will see a hole in the ground, drop down into the hole and use the yellow bar to swing ahead and collect an extra life sitting on the platform in front of you.
Continue on with the mission and you will come to a door that you will need to unlock using the mechanisms, once unlocked go through and on the far left side will be a codex page.
Moving up in the lift to the next room you will see a steel ball in the air that will require you to break the chain. To reach the chain you will need to drop behind the skull statue and activate the skull pedestal, from there you can use the boosters on each side of the room to reach the chain. Before or after you break the chain use the boosters to launch you high up and break the wall on the opposite side to the skull, inside will be an album.

After breaking the chain and collecting the album drop down into the hole and take the next lift downwards.

NOTE I: In this area you will have 2 items to collect.
NOTE II: One of the next secrets can be a pain to reach so don't worry if you miss it as you can come back at the end when we unlock fast travel, that way you can repeat it as many times as you need until we collect it. When you step off the lift follow the path around the hole and you will find a praetor suit token on the other side.
 
Now for the difficult part. Stand on the edge of the hole that's in the center of the room and make sure you stand on the side nearest to the praetor suit token. About half way down the hole is a wall you can break through, you're best to look at the images below to see the wall as it can be difficult to spot otherwise.
Once you see the wall, drop down and use the first dash to slow your fall and aim, then use the second dash to break through, don't bother with jump as it doesn't quite work.
If you miss the wall then as far as i'm aware you can't get back up without fast travelling to the throne room.

Continue the mission now until you finish draining the water.

After draining the water make your way out of the sewer following the mission marker, and just before you enter the next room you will come across a codex page, then from there drop down into the room and you will also find a mastery token next to the main doors.

Now continue the mission into the lower level for the main fight, after the fight you will unlock fast travel, so if you missed the earlier secret go back and try again by fast traveling to the Throne Room. That will complete this mission. Don't forget to complete your challenges if you want the achievement.

NOTE: We are now in the fortress for the last time until we reach the end of the campaign. If you're missing any slayer outfits i would suggest collecting them instead of the praetor suit token because from this point on you will no longer collect sentinel batteries. Current items to collect:

• 1 Praetor suit token
  
• or
  
• 1/2 Slayer Outfits
• 1 Arc Broadcast Log

Once again the last praetor suit token can be located just past the Demaykr, but just remember to focus the slayer outfits first.
As we have two more sentinel batteries left we will also collect the classic slayer suit. It is located on the top level above the Demaykr.
You will collect this when activating the portal to the next mission.

We will come back one more time at the end of the campaign and collect the last two items which will be another slayer suit and the Demaykr. Time to start another mission

NOTE: Ok, this is a good mission and one i enjoyed quite a bit but it can be tricky to find some of the items so don't move on too fast. There is no slayer gate on this mission so we won't be looking for a key. I will guide you as best i can as always. This mission contains:

• 2 Codex Pages
  
• 1 Album
  
• 3 Praetor Suit Tokens
  
• 2 Secret Encounters
  
• 2 Mastery Tokens
  
• 1 Automap
  
• 3 Doomtoys
  
• 3 Extra Lives
  
• 1 Cheat Code
  
• 1 Sentinel Crystal

 
Begin the mission and moving straight ahead you will come to a stairway, at the top of the stairway follow it around to the left side and at the end of the path you will find a sentinel crystal, watch out for the mancubus and other demons along the way.
After collecting the sentinel crystal, continue the mission and climb up into the gap on the opposite side of the stairway as required. After entering and clearing the first room don't drop down and instead use the top platforms and follow them around to find a codex page just around the corner.
NOTE: In this area you will have 2 items to collect. Proceed and make your way outside. Once outside defeat the Tyrant and other demons and then activate the green plate. Do not exit the main gate just yet and instead look to the left from the green plate and use the yellow bars to swing up and across to the wall next to the gap high above, from there jump and dash into the gap and inside you will find an extra life and doomtoy.

Continue the mission until you have passed the large room with the lava and sinking platforms, this is the area where you have to shoot the 4 eyes just after your little journey in the cage.

NOTE: In this area you will have 4 items to collect. After destroying the 4 eyes and the brain looking thing climb the wall behind it and at the top take a right and follow it around to find a praetor suit token just around the corner.
From the praetor suit token head back and take the other path under the crusher past the green target and in the next room on the opposite side will be a mastery token sitting in the alcove.
Once you have the mastery token take the nearby stairway and in the room at the top you will see another praetor suit token, you can't miss it.
Immediately after collecting the praetor suit token look to the right side and drop down off the edge to find the automap below.
NOTE: In this area you will have 4 items to collect.
Secret Encounter:
For this encounter you will be attacked by 1 mecha zombies, 1 hell knight. After collecting the automap continue back up and you will come to a large gap, do not jump across. Underneath you over the edge is a breakable wall, you will need to drop off the edge and dash into the wall beneath you and inside you will find the secret encounter and a doomtoy. Do not jump across to the opposite side otherwise you cannot reach the breakable wall.
From the secret encounter follow it all the way through and back around to the large gap, this time jump across to the wall opposite and from there follow the mission objective. The mission will direct you to jump around a corner to another wall so jump across and make your way up and when at the top of the wall follow the path around to the left to find an extra life.
NOTE: In this area you will have 2 items to collect. Continue the mission and you will come to more walls that you will need to climb, make your way up the walls until you reach a dead end room.
In the room you will notice cages moving up through the chutes, stand on one of them to take you up into another room.
Once you're up in the next room you will notice the crushers slamming to the ground, as the first crusher lifts look on the right wall and you will see that you can break through and inside you will find a mastery token and a doomtoy.

NOTE: In this area you will have 3 items to collect.
Secret Encounter:
For this encounter you will be attacked by 3 zombies, 1 baron of hell. Move through the crushers and into the next area, clear the demons and from the centre of the room face the large gateway. On the left side of the room you will notice a cage moving upwards through the chute, use the cage to lift you up and dash over to the small piece of wall opposite, from there jump through the gap at the side of you that is lit up green.
 
Once you have dropped through the gap, activate the skull pedestal and then go back through the crushers and into the previous room, from there you will see the gate has opened which gives us access to the secret encounter and an album vinyl a little further on inside.
 
From the album vinyl you can go straight through into the main room again, from there head through the crushers on the far right corner into another room. Inside the room you will encounter a marauder and a whiplash, after killing them you will notice more cages moving through the chutes so this time drop down one of the chutes into to a room below and inside you will find another album vinyl.
After collecting the cheat code head back up into the room above and follow the passage along and at the end around the right corner will be a codex page. Now continue the mission by activating the nearby skull pedestal.
NOTE: In this area you will have 2 items to collect. After activating the skull pedestal you will have opened the main gate, head through the gate and clear the room of demons which includes a couple of doom hunters.
Once the room has been cleared you will see an extra life up above on a small platform in the corner, it is located on the left side from where you entered the room. Use the yellow bars to swing up and collect it but do not drop back down just yet. From here we will move to the next item which will also be our last for this mission.
 
So immediately from the platform jump across to the next platform nearby and then onto the further platform where the crushers are located. Go through the crushers and at the opposite end you will find another praetor suit token, this path will also take you towards the mission objective so you shouldn't miss this.

That completes all items for this mission. Continue and melee the statue to unlock fast travel, then you can port or finish the mission and move on to the next.

NOTE: Another tricky mission to navigate and once again no slayer gate on this one. As with the last mission, again i would say don't move on too fast as a lot of items are close to each other here and some can be missed, at least until fast travel unlocks so take your time. This mission contains:

• 3 Codex Pages
  
• 2 Albums
  
• 3 Praetor Suit Tokens
  
• 2 Secret Encounters
  
• 1 Mastery Token
  
• 1 Automap
  
• 3 Doomtoys
  
• 3 Extra Lives
  
• 2 Cheat Code
  
• 1 Sentinel Crystal

NOTE: In this area you will have 4 items to collect.
Secret Encounter:
For this encounter you will be attacked by 2 pain elemental. The moment you start the mission follow the path ahead and as you go along the bridge stop at the second statue on the left side, look over the edge of the bridge and just below you will see a booster that you can drop down to and boost across to the platform opposite. On that platform you will find an extra life.
From the extra life jump over to the next platform with the rotating flames and on there will be a mastery token.
 
Now again from the platform you are on jump across to the smaller platform opposite connected to the wall, on there will be an album vinyl and the secret encounter.

Move on from the encounter back onto the bridge and make your way across the platforms on the opposite side and up into the first room.

Once inside clear the first room of demons and as you make your way into the next area you will find a sentinel crystal on the right side tucked around the corner.
NOTE: In this area you will have 4 items to collect.
Secret Encounter:
For this encounter you will be attacked by 1 hell knight and 1 cyber mancubus. Proceed into the next room and battle it out with the demons and another doom hunter, once clear continue to follow the mission marker and as you go through the next passage you will come across a codex page in the corner, you can't miss it.
 
Immediately from the codex page continue further down the passage and on the right side you will find a breakable wall, break through and inside you will find a doomtoy along with the secret encounter.
 
Now after the secret encounter you will come to a big drop. The next item is underneath you but to reach it you will need to jump across on to the bloodied platform first and then face the direction you jumped from. You will see a breakable wall lower down so jump across and break through the wall to collect the album vinyl, but be careful here because if you fall and miss the item you will need to fast travel back at the end of the mission.
NOTE: In this area you will have 5 items to collect. After the previous item you will drop down into the main room, once again clear it of demons and then follow the mission marker into the small opening. Once you enter the opening make your way through and you will come to another codex page.
 
Now keep going and immediately after the codex page on the left side will be another breakable wall, break through to find another album vinyl.
 
Continue on and you will come across another big drop with rotating flames/platforms. Once again the item is beneath you so you will need to jump across to the opposite platform a little lower down, then face the way you jumped from and directly opposite you should see a small opening in the wall. Jump and dash across to the opening to collect a doomtoy.
 
Now continue and make your way up to the very top using the platforms. Once at the top we will find two items, first you will see the automap in the opening and then from the automap face towards the rotating platforms you climbed and you will see an extra life at the top of the middle beam. After collecting both items continue the mission to the lift.

NOTE: In this area you will have 2 items to collect. Continuing the mission you will head upwards on the lift, when you reach the top you will need to jump across to the opposite side to the green lit opening. Before heading to the opposite side jump across to the left set of spikes and break through the wall, inside will be a praetor suit token. From there continue across to the green lit opening and collect the codex page.
NOTE: In this area you will have 3 items to collect. After collecting the codex page continue the mission and you will come to a large booster that shoots you high up in the air, jump on the booster and half way up you will find a breakable wall, break through to find another doomtoy.
Now jump on the booster again and at the very top you will see an extra life floating above the hole, you can't miss it.
At the top of the booster continue and make your way into the next room, jump across the large gap and once across make your way around to the other side of the machine/lift and there will be a praetor suit token waiting for you.

Continue the mission all the way until you reach the very top area outside.

NOTE: In this area you will have 2 items to collect. When you reach the outside area just after the lift you will encounter almost every type of demon, clear them up so we can proceed. After clearing the demons go back to the lift where we entered the area and drop down the shaft to a level just below you, inside will be a cheat code. Just be careful here because if you drop too far down you will die/respawn.
 
After collecting the cheat code you will find another praetor suit token at the end of the passage where you exit out, you can't miss it.

That is all items collected for this mission, you can now complete the mission or fast travel to any items you may have missed.

NOTE: This is by far the best looking mission, it's truly beautiful, however, it is also one of the worst missions because it's full of platforming. This is difficult to navigate so follow carefully and i will try my hardest to point you in the right direction. This mission contains:

• 4 Codex Pages
  
• 2 Albums
  
• 2 Praetor Suit Tokens
  
• 2 Secret Encounters
  
• 2 Mastery Tokens
  
• 1 Automap
  
• 3 Doomtoys
  
• 3 Extra Lives
  
• 1 Cheat Code
  
• 1 Blue Orb

Start the mission and as you walk outside look to the left next to the tree to find a codex page.

Continue the mission through all the hoops/portals and platforms until you are back inside.

NOTE: In this area you will have 2 items to collect. Once you're back inside you will need to shoot a few targets, so first shoot the green target and jump across the gap. After that turn around towards the gap and up in the ceiling is another green target, shoot it and this will activate a lift in the centre. Use the lift to take you up a level and follow the path along and at the end jump across to the platform in the centre of the room, on the top will be a mastery token.
 
Once you have the mastery token immediately look down towards the back of the platform and you will see an automap, collect the automap and then move along into the next area.

After clearing the next area make your way across the coffin shaped floating walls and break through into the chute and follow it through.

NOTE: In this area you will have 2 items to collect. Now for more platforming, also see the screenshots to help you out a bit with this part.
Once you're through the chute head towards the mission marker via the platforms. The mission will direct you to break through the green vent, but do not break through just yet and instead climb up to the left platform nearby and then from there jump across to the opposite platform to find a codex page. Immediately from the codex page jump up another level to the left side and inside will be a breakable wall with an album vinyl behind it.
Now continue and break into the vent and once inside the vent follow it through. Just before you exit the vent there will be a chute directly above you with an extra life hiding inside.
Secret Encounter:
For this encounter you will be attacked by 2 zombies, 2 maykr drones, 1 cyber mancubus. Now continue and exit out of the vent and then melee the cube nearby, once the cube is in place climb on to the cube and jump into the opening above and inside will be the secret encounter, you will need to be quick with this encounter.
After the secret encounter melee the statue and swing across to the far wall, from there if you look up to the next wall you will notice an album vinyl on the platform above it, use the nearby bar to swing up and collect it.
From the album jump across and break through another vent, follow it through to the left and climb up but then immediately turn around in the direction you came from and you will see a mastery token in front of you.
Now exit the chute and destroy the buff totem along with all the demons. Above the chute that you entered the room from is a platform high up, you will need to stand back away from the chute to see it properly. On the platform is a codex page and to reach it you will need to use the yellow bar to swing up, it is located on the left side pillar as you face the platform, the screenshots should give you a better idea.

Continue the mission until you're back outside.

When you're outside you will see the large rings in a small cut scene. After the cut scene do not use the booster and instead on the right side of the booster over the edge of the platform will be a breakable wall directly below you. You can't see it from above so you will have to drop off the edge, turn around and then dash into it to collect a doomtoy.
If you miss and fall you can just respawn and try again, just don't die.
Now use the booster to launch to the other side and when you land follow it all the way around to the right side corner. In the far right corner climb the rocks and use them to jump across to platform just inside the structure, from there break through the wall and inside will be a praetor suit token. Now continue and use the next booster.
After landing from the booster again follow it around to the left side and tucked in the far corner next to the building will be a codex page.
 
Immediately from the codex page turn around and face the direction you came from and you will see just ahead a platform up above with a doomtoy located on the top.
Now use the booster leading to the orange ring.

NOTE: In this area you will have 2 items to collect.
Secret Encounter:
For this encounter you will be attacked by 1 doom hunter, 1 spectre, 1 whiplash. When you land after using the booster you will have to swing across to the next area. When you reach the next area stand on the edge of the platform and look outside to the right, you will see a breakable wall, break through it to find an extra life and the secret encounter.

Continue the mission until you reach the next booster.

This next part is a pain. When you use the booster aim directly for the landing spot you want and ignore the walls, as you get closer shoot the green target and you should make the landing no problem. From there you can proceed to activate the ring. After activating the ring continue ahead and when you exit outside immediately look to the left just off the edge of the platform and you will find a doomtoy hiding away, jump across to collect it.
Now make your way across to the purple ring using the final booster.
After landing in the next area after the booster clear it of all the demons and in the centre of the area you will find a blue orb.
NOTE: In this area you will have 2 items to collect. After the blue orb head inside the building and before entering the lift collect the praetor suit token at the back of the room, you can't miss it.
 
Continue up in the lift and activate the final ring, after activating the ring you will head back outside and down a few steps towards your next booster, as you go down the steps, on the left side will be a breakable wall, jump over to it from the steps and inside will be a cheat code.
Proceed now to the final area and make your way through the building towards the boss fight. You will come to an area full of water and at the bottom of the water on the far side will be an extra life. Collect the extra life and then on the opposite side will be a breakable wall you can use to drain the water and continue your final path to the boss. That completes all items for this mission.

Time to move on to the final mission

NOTE: The final mission, finally! This is pretty quick and easy, you shouldn't have any issues finding everything on this one. Very few items here and most are extra lives. This mission contains:

• 1 Codex Page
  
• 1 Automap
  
• 4 Extra Lives
  
• 1 Blue Orb

Start the mission and just around the corner on the right side break through the wall and climb up into the vent inside, follow it all the way through to find an extra life.
After the extra life jump over to the next area and battle it out with a doom hunter, tyrant and many other demons. Once the area is clear then make your way through the broken wall into the next area and directly in front of you will be an automap.
Continue on and take a big leap across to the opposite building, when you land look across the gap on the left side and you will see another breakable wall. Break through the wall and climb the wall inside, then follow it through to find another extra life at the end.
This should then bring you out to the upper platform.
NOTE: In this area you will have 2 items to collect. Continue the mission over to the next building and when you land follow it all the way around until you reach the elevators.
The elevator on the left side is out of service but has a green target inside, peak through and shoot it.
Now climb up into the elevator on the right side and when you reach the top you will see a codex page in front of you, immediately after the codex page look into the other elevator and you should be able to climb through and collect another extra life located inside.

Proceed onward with the mission and you will reach a small cut scene where the bridge/platform gets destroyed. After this jump across to the opposite side and clear the room of demons, this room should contain a buff totem that you need to destroy.

After destroying the buff totem make your way up to the next floor and follow it around to the right side. As you walk around to the right you will notice a blue orb in the central room.
 
To access the orb keep following the path around and move up to the next floor by climbing the wall towards the quest marker, once you reach the next floor do not follow the quest marker and instead follow the path to the left side all the way around. At the end of the path tucked in the corner will be an open shaft, enter inside and break the vent to drop down and collect the blue orb in the room below.

Continue the mission all the way until you have jumped across a few buildings and have a huge battle with 3 tyrants and tons of other demons, this should be in the last building you enter and it's about 3 or 4 stories high.

After the big battle make your way up to the third floor and as you go up the stairway face the room covered in the flesh like material and around the back near the windows will be a breakable wall, break through and drop down to collect the extra life.

That completes all items for this mission and the entire campaign, phew! Now go kill the final boss!

Thank you for following my guide, i hope it has served you well.

NOTE: This mission is tons of fun and much harder than the original campaign. No doomtoys or cheat codes for this one but plenty to collect along with one item that is missable. This mission contains:

• 1 Automap
  
• 4 Codex Pages
  
• 4 Extra Lives
  
• 5 Blue Orbs
  
• 3 Secrets
  
• 2 Secret Encounters
  
• 1 Slayer Gate Key
  
• 1 Support Rune

 
NOTE: In this area you will have 2 items to collect. Begin the mission and continue until you pick up the blue key, head upwards to clear the enemies on the upper level and once clear it will direct you to activate the button on one of the computers nearby.
Activate the button but do not head outside, instead head out the middle doorway towards the door that says red access and head down the stairway nearby, at the bottom will be your first codex page.
 
After picking up the codex page stay on the lower level and make your way outside, just at the side of the door that leads out will be a blue orb that you can now pick up, this is the door next to where you found the blue key.

You will need to come back here shortly but for now continue the mission over to the other side.

After jumping across to the next area you will need to clear it and then move on to another area where the red key is located. Clear all enemies and then make your way up into the ventilation shaft, you can access the shaft using the platform opposite the door you used to enter the area.
Following the shaft drop down into another part of the shaft and turn left, you will find an Extra Life located in the shaft above further along. Now continue and drop out of the shaft to grab the red key.
Now you have the red key clear the enemies and make your way back outside, after killing the marauder do not proceed with the mission and instead jump back across to the starting area where the blue key was located.
On the upper level you can now gain access to the red access door, this is located at the top of the stairway above where you found the codex page.
There isn't much inside other than ammo but it's a secret area non the less.

Now continue the mission back across to where the marauder was and head into the elevator.

NOTE: In this area you will have 2 items to collect.
Secret Encounter:
For this encounter you will be attacked by 1 mancubus, 2 carcass, 1 zombie. Once you exit the elevator look to the right and just over the edge of the platform you will see a wall you can grab, use it to drop down to the platform underneath you where you will find the secret encounter.
 
After the secret encounter go back up using the same wall and then proceed to jump the small gap to the other side (watch out for the fan). At the other side you will see the green mechanism, as you face the mechanism head left and you will find another codex page on the platform further up.
NOTE: In this area you will have 2 items to collect. Continue the mission and use the mechanism to get over to the next area with the electrified floor. Once in the next area clear it of enemies and on the opposite side to where you entered will be a small shaft you can break through, inside will be a secret doom bunny.
 
If you face the shaft again and look at the fencing to the right of it, jump over and inside will be a blue orb hiding low down.
Now launch yourself across to the other side using the fan and grab the wall, drop down from the wall and clear the enemies. Once it's all clear face the door on the lower level and to the right of the door you will find a platform that leads around the building and on it at the end is a codex page.
Proceed upwards with the mission and you will encounter a big battle with at least a doom hunter and a baron of hell or two, after the big battle head into the building and you will find a codex page sitting behind the steps in front of you. You will also find a small easter egg nearby on the dead body.

Now continue the mission through until you reach the room full of tentacles, this should be right after another big battle which is just after the short cut scene.

NOTE: In this area you will have 3 items to collect. At the room full of tentacles the mission will direct you through to the left room, ignore that for now and go straight ahead past the slayer gate and straight in front of you will be the auto map.
 
Immediately from the auto map climb the crates nearby and look down over the edge of the fence and you will see swing bars on the wall, use them to swing around to the right side and break through the vent to find the slayer gate key at the end (watch out for the turret).

 
To gain the support rune you will need to complete the slayer gate, good luck!

NOTE: In this area you will have 3 items to collect.
Secret Encounter:
For this encounter you will be attacked by 5 spectre, 1 zombie. After the slayer gate continue the mission into the next area and clear the room as normal, once clear make your way up to the room above where you will find the dive suit, above the dive suit on the back wall you will see a vent you can break through to find a secret area and a piece of armor.
 
In that same area press the button on the computer nearby, this will unlock the tunnel under water leading to the next secret encounter. Head back down to the lower level and dive into the water, swim through the left tunnel and follow it through to reach the room with the secret encounter.
 
After the secret encounter go back under water and swim to the opposite side of the room, under the platforms where you entered the room you will find a vent on the wall that you can break through not far from the air canister and this will lead you to a blue orb.
Make your way outside and you will need to activate the mechanism to get across to the wall. From the wall jump over to the platform but ignore the mission marker and instead follow it to the right to find an extra life at the end of the path.
Continue on with the mission and you will soon reach a room with electrified floor and a turret. At the back of the room is more water, grab the dive suit next to the upper door where the mission marker directs you and then head into the water and you will find a blue orb sitting inside the large broken pipe below.

Continue the mission past the cut scene and swim through the water into the under water building.

NOTE: In this area you will have 2 items to collect.
WARNING: If you climb out of the second entrance and continue the mission you cannot get back to this location, even with fast travel. Ok, for this part follow carefully.
Make your way through the under water building and it will direct you to exit back out and into the water. Once in the water it will direct you to another entrance, swim over to the next entrance and climb up but immediately drop back down into the water; this will hit a checkpoint and unlock another entrance further along, head over to the next entrance and that will allow you to follow it along and grab the 2up extra life.
If you don't climb up to the second entrance first then the third entrance will remain locked.
  
After collecting the extra lives proceed with the mission into the centre of the structure. Just below the elevator under the water will be a breakable floor with a blue orb inside and that shoiuld be your final item of the mission.
 

NOTE: Another good mission that will definitely test your eyesight, and I think a little less to collect this time around. Fairly straight forward with some slight backtracking but no slayer gate on this one. This mission contains:

• 1 Automap
  
• 4 Codex Pages
  
• 3 Extra Lives
  
• 2 Blue Orbs
  
• 5 Secrets
  
• 2 Secret Encounters
  
• 1 Support Rune

 
Begin the mission and make your way through until you reach the giant tentacle, kill it and jump across then take a left and you will find a breakable wall just past the flames lower down, this will lead you to the support rune for your first item.
NOTE: In this area you will have 3 items to collect. From the support rune head towards the fiery chains and climb the rocks, jump across to the other side and drop down. Grab your rad suit and drop into the water, immediately look behind you to find a codex page hiding in a small gap.
 
Now follow it through and as soon as you exit the water you will find the automap on the platform you climb out onto.
 
Continue over to the upper platform and in the far left corner is a breakable wall that contains an extra life. Kill the enemies and then collect the extra life.

Now continue the mission and activate the skull pedestal, then head through the main gates and into the circular area that contains the tomb. Two gates will open near the cubes so take the right side first.

NOTE: In this area you will have 2 items to collect and find 1 secret.
NOTE: For this encounter you will be attacked by 3 imps, 1 baron of hell, 1 mancubus, 1 cacodemon. Head through the right side gate and follow it along until you reach the green hound, complete the battles following the hound until the area is clear and you're able to freely roam, the battles should finish at the main gate.
At the main gate do not unlock it just yet, instead go back following the path you came from towards the secret encounter, skip past the secret encounter and follow the path even further; as you pass through the doorway you will see an arch shaped rock with a codex page sitting on the top that you can climb up and collect.
 
Once you collect the codex page head back to the main gate and as you enter that area you will see the skull pedestal in front of you and the gate to the right side, head left and follow the path into the swamps.
In front of you should be two small platforms, one with a poisonous egg sitting on it. Climb up to the egg and use that platform to jump over to the yellow swing bar in the distance and then swing over to the wall and climb up.
 
After climbing the wall and follow the path around dropping down into the nearby hole, follow it along and climb the wall then melee the cube at the top, this should unlock the nearby gate and allow you to access the secret encounter via the path around the side.

Now head back and continue the mission, go through the main gate and make your way to the very top past the unstable platforms and the yellow swing bars.

At the very top you will encounter a turret along with your first possessed demon, after clearing the area look on the back wall and tucked in the corner on the lower part of the area is a wall you can break through to find a blue orb.

Now complete the arena further up and get yourself ported back to the central tomb area, and this time head through the left gate as that's your only option.

Follow the path through the left gate and you will come to a turret and a yellow swing bar, destroy the turret and use the swing bar to reach the other side where you will find another turret to destroy. From the second turret look at the rocks opposite and you will see a hole lower down that contains an extra life, simply jump across to collect it.

Continue the mission until you get past the marauder and destroy the buff totem, then melee the cube into place and move into the next area.

After destroying the buff totem and moving the cube into place, climb up and then drop down into the next open area with low visibility and another green cube outline. Follow the area around to the right side and at the very back will be a small amount of water that you can dive into and break through a wall to find another extra life.

Continue on and get the cube into place and then move into the next area that has almost zero visibility.

After battling another doom hunter in the low visibility area, melee the mechanism and swing across to the upper section further along. When you land immediately turn around to find another secret area through the breakable wall.
NOTE: In this area you will have 1 item to collect and find 1 secret. Now you should be situated next to the secret encounter, ignore that and activate the skull pedestal nearby and then use the jump booster to reach the opposite side. At the opposite side clear the area and behind the large skull you will find a small amount of water that you can drop down into that will take you to a secret area and a codex page at the very end.
 

NOTE: In this area you will have 2 items to collect.
NOTE: For this encounter you will be attacked by 2 whiplash, 2 imps, 1 baron of hell, 1 mancubus. After collecting the codex page continue on with the mission back to the main gate further along.
Do not unlock the gate just yet and instead head left as you face the skull pedestal and follow the path all the way around and through a green breakable wall to find a secret area and another skull pedestal.
Activating the skull pedestal will unlock the nearby gate whilst the cube will drop down and unlock the secret encounter. Go ahead and clear the secret encounter opposite the cube and then proceed back to the main gate and open it up.
After opening the main gate and heading inside, activate the mechanism and race your way to the top before you die. When you reach the very top after the jump booster continue forward and take a left and you will see a wall you can break through to find a secret area containing BFG ammo.
Continue from the BFG ammo and use the yellow bars to swing across and climb up, once you're up after climbing the wall you will see another wall on a large pillar out in the distance away from the building; jump across and climb the wall and you will see a codex page on another platform opposite as you face the building. Simply jump across with a big double dash to collect it.
Now continue the mission and proceed to the upper arena area, once up you will find a blue orb sitting on a block at the very back of the area next to the portal, this should be your final item for this mission. Now go beat some bosses and move on to mission three!
 

NOTE: This is the final mission for this DLC and what can be a tough boss fight at the end. It can be a little difficult at times to navigate this mission so I will try to explain as best I can but overall it should be straight forward enough. This mission contains:

• 1 Automap
  
• 5 Codex Pages
  
• 4 Extra Lives
  
• 4 Blue Orbs
  
• 1 Secret
  
• 2 Secret Encounters
  
• 1 Support Rune
  
• 1 Slayer Gate Key

NOTE: In this area you will have 5 items to collect.
Secret Encounter:
For this encounter you will be attacked by 3 zombies, 1 spectre, 1 cyber mancubus possessed. The first lot of items are fairly close to each other which makes life a little easier.
So, begin the mission and proceed through until you reach your first big battle with the marauder and tyrant, this should be the area just after the green exploding platforms. Once clear continue through the path and you will notice the slayer gate key up above, ignore that for now and in the next area follow it around to the left side and up onto a pathway, at the end of the path will be an extra life.
 
Now go back and melee the tree that will allow you to climb upwards, once you're up climb even further up onto the left side platform and follow the path ahead to find a breakable wall with another extra life behind it.
 
After collecting the extra life head back towards the tree but follow the path around to your right and you should be able to jump across to the opposite platform and collect the slayer gate key on the other side.
After collecting the slayer key go back once more to the area at the top of the tree and this time go straight ahead from the direction you originally climbed up from, on the right side wall will be a breakable wall and inside you will find the first secret encounter.
 
From the secret encounter head towards the mission marker and you will see a waterfall below it in the lower section, behind it is a breakable wall containing a blue orb.
NOTE: In this area you will have 2 items to collect. After collecting the blue orb head towards the back of the area away from the mission marker, you will find the slayer gate located there and you will need to complete it to gain the support rune.
 
Continue further along past the slayer gate to find the automap sitting at the dead end.

Now continue the mission up and across the trees etc.

Once you're past the trees continue to follow the path and you will come to a group of mecha zombies next to a cueball, climb up to the path above them and further along you will come to the end of the path and a big open area. Look down directly below you and you will see a codex page you're able to drop down to and collect, just be careful as there are tentacles surrounding the codex page.

After the codex page head back and work your way up to the mission marker, proceed with the mission until you reach the platform next to the 2up extra life.

Once you're on the platform face the exploding green platforms and look on the left wall, there is a breakable section that you can break through and collect the 2up extra life.
Continue the mission until you come to an area full of platforms and directly in front of you below will be a blue orb, not quite a secret but you can collect it regardless.
Proceed to activate the platforms and complete the small battles. After completing the two battles you will then be able to reach a breakable wall high up on the opposite side to the quest marker, use the platforms to reach it and find another secret area.
NOTE: In this area you will have 2 items to collect. Continue the mission following the mission marker and you will make your way outside, the mission will direct you to activate the podium ahead but if you jump over to the platforms on the right side you will find a codex page
 
From the codex page head to the opposite side and on another platform you will find a blue orb.
NOTE: For this encounter you will be attacked by 2 zombies, 1 blood maykr, 1 marauder. After collecting the blue orb and codex page you can now activate the podium and boost to the other side. At the other side make your way through and battle it out in another arena and at the back of the arena will be the secret encounter. To gain access to the secret encounter look directly up above the second podium nearby and there will be a green target you can shoot that will drop the laser fence and allow you access.

Now continue the mission by activating the podium next to the secret encounter and outside will be a booster you can use to jump high up and grab a floating wall which will allow you to proceed.

Once you land on the top platform after swinging across, head to the right towards the mission marker and on the left of the third podium will be a codex page. Now activate the podium and move on.
After defeating the two tyrants and doom hunter, head through the left door and it will take you to an area full of pinky's and on the central platform will be a blue orb.

Continue through and you will need to activate the mechanism on the opposite side, this will activate the booster near the central door and allow you to boost across towards the mission marker.

NOTE: In this area you will have 2 items to collect. As you boost across you will need to shoot the green target located upwards in the center of the area, this will drop a swing bar down so you can make it to the other side and break through the wall.
As soon as you land and break through the wall turn around and look up towards where the swing bar was located, you will see another green target that you can shoot. Shoot the target and then jump back to the other side and now you can access the central door to collect the codex page inside.
 
After collecting the codex page you can now again jump back across using the mechanism once more, this time when you land on the other side you will find the final codex page in the far right corner of the room. This will be the last item for this mission and fast travel should now be unlocked.

Now go beat 10 bags of hell out of the final boss and compete this DLC once and for all.

NOTE: New day, new DLC. Not the greatest DLC but it is still fun with a few changes I'm still not so sure about. These missions are very light on items so not much to collect at all and doesn't take up too much time.
There are new escalation encounters which are like the slayer gates but they are not hidden or secrets of any kind so I won't be adding them to this guide. There is only one escalation encounter per mission, but after completing each one be sure to activate it again for a second harder run which will give you a slayer suit upon completion. Aside from that have fun and enjoy the new content. This mission contains:

• 1 Automap
  
• 2 Codex Pages
  
• 4 Extra Lives
  
• 1 Blue Orbs

NOTE: In this area you will have 2 items to collect. Start the mission and make your way through until you reach the area that spawns a large tentacle out of the small pool of water. This is the next area after destroying the buff totem and your first encounter with armored barons.
Clear all mobs and when heading towards the mission marker you will notice an extra life behind a locked gate.
To access the gate stay outside and head to the opposite corner diagonally and you will find a skull pedestal tucked behind the wall, activate it to unlock the gates and give you access to the extra life.
 
Now follow the mission marker inside and drop down the hole at the back of the room. Make your way around and up until you reach the hole in the wall with the yellow swing bar going across it that leads outside. Do not swing across and instead use the booster below you inside the room to reach the highest platform opposite, on there will be a blue orb for you to collect.

Continue on with the mission into the next zone until you reach the encounter with the stone imps for the first time.

After cleaning up the stone imps proceed with the mission and activate the skull pedestal further up, this will activate the booster nearby. When at the skull pedestal if you face it and look to the opposite far side (in the same direction the booster sends you) you will see an extra life sitting in a sewage entrance/exit just beyond the broken bridge on the back wall. Boost and grapple up across to the broken bridge and jump over to the extra life, after that head back up to the broken bridge and continue the mission.
NOTE: In this area you will have 3 items to collect. Now move into the next zone and once again clear all the mobs. Once clear continue and you will come across some grapple points that will get you further along, the one high up above you is not active but has a 2up extra life above it which you collect after the automap. To collect the automap simply use the other grapple points and swing bars to make your way around and up, once you're up on the top platform after the swing bar you will find the automap on the right side ready to activate and upload.
 
After the automap continue on and you will see the higher grapple point which will now be active, use it to reach the extra lives above.
 
Once you have collected the extra lives go back and jump across the gap where the extra lives were floating and immediately in front of you on the right side will be the first of the codex pages.
Continue the mission all the way to the very end where you meet the five Maykr. In the center of them you will see a crystal of some sort and next to it will be the second codex page which is our last item for this mission.

That is all for this mission, let's move on.

NOTE: Possibly my favourite mission out of the three but once again low on items and secrets, nothing much else to add I'm afraid.
Once again I will not be adding the escalation encounters to this list because they are unmissable and not hidden. Just remember you will need to activate the same escalation encounter again once you complete the first so you can claim the second and get your armor set. This mission contains:

• 1 Automap
  
• 4 Codex Pages
  
• 3 Extra Lives
  
• 1 Secret

NOTE: In this area you will have 2 items to collect. Begin the mission and immediately head left and look over the edge of the platform you're on to find a codex page hovering on the floor below.
 
Once you have the codex page head to the far right side of the area which looks to be a dead end. Hiding behind a truck at the very edge of the map will be an extra life.

Continue with the mission.

In the next area you will come to a narrow passage way, this is not far ahead it's just after a few wall jumps. Kill the stone imps and mancubus that spawns and when you continue you will get a small cut scene showing you the grapple points to get across to the other side.
After the cut scene face towards the red door and tram, and on the lower right side just tucked around the corner is the automap.
After the automap proceed with the mission and make your way over to the escalation encounter. Complete the escalation encounter and drop down into the hole that the mission marker directs you to, on the left side as you move out of the short passage way will be the next codex page.
Continuing the mission you will come to a point where you will need to swim through water, proceed all the way through and past that point until you get outside where you are presented with another small cut scene, this time showing you the broken corner of a building as your target.
When the cut scene ends head over to the left side and you should find a codex page behind the pillars under the building.
NOTE: In this area you will have 1 items to collect and 1 secret to find. Make your way to the very top of the building and you will encounter two revenants just before reaching the large hole in the building wall. After killing the revenants head forward and on the far right side opposite the hole will be a breakable wall, inside is a secret which contains BFG ammo.
 
Now jump out of the building to the small hanging platform opposite and make your way across into the next building. In the next building clear the mobs and opposite where you entered is a small room with an extra life inside, access it by breaking the wall at the side further along. From here continue the mission.

After jumping the large gap into the next area, you will notice a red locked door. Ignore the door for now as we will fast travel later and come back to collect the extra life inside.

NOTE: In this area you will have 2 items to collect. After passing the red door to the next area, prepare for a big battle and clean it up. Once the room has been cleared follow the mission marker into the elevator and when you exit at the top you will find the codex page on you right side.
 
Now do not continue the mission just yet as this will end everything, so instead fast travel back to the location called 'Lockdown'. At the lockdown location once again jump the gap and enter what used to be the red locked door on the right side, inside will be an extra life which is the last item we needed to collect. Now you can continue and complete the mission and move on to the third.

Move on to the third mission.

NOTE: Nothing much to add to this mission, pretty much everything from the previous missions apply. As mentioned before, this DLC has very few collectables compared to the rest of the game, which makes life easier for me but less fun for those treasure hunters out there.
The final mission which comes after this is a boss fight only, no collectables are found beyond this mission so this is the last one for this guide. This mission contains:

• 1 Automap
  
• 4 Codex Pages
  
• 3 Extra Lives
  
• 1 Secret

NOTE: In this area you will have 3 items to collect. Start the mission and use the booster to jump across, then follow the path upwards to find the first codex page half way up at the second bend.
 
Immediately after the codex page on the left side is a platform you can climb, climb up and break the wall and follow the path along to find an extra life at the very end.
 
Now complete the escalation encounter in the next area, once complete follow the mission marker and just before the green wall that you need to break through will be the automap.
 
After the automap smash through the green wall and immediately in front of you will be a platform you need to reach at the top left side. Use the platform on the right side to jump across and collect the 2up extra life that's sitting there.
Continue the mission and further along kill the large tentacle. After killing the tentacle continue along the path and as you enter the next area you will notice an extra life trapped behind spikes up in the rocks on the right side wall. Further along on the same side is the entrance to it, but you will need to use the rocks on the left side to jump and double dash across to get in. It's a long jump.
Proceed with the mission all the way to the tank. Climb into the tank you will reach a cut scene where the tank will fire you into the wall and into the next zone. Immediately after landing you will see a codex page to the left of you.
After collecting the codex page make your way through until you reach the platform where you encounter two marauders. Kill the marauders and jump over to the next platform, straight ahead of you at the back wall will be another codex page.
Now make your way around through the mobs and you will eventually encounter a doom hunter. Kill the mobs and the doom hunter and then enter the doorway that the doom hunter came from, this should be the first door in front of you when crossing the bridge.
At the back of the room behind the pillar is a button you can activate, activate it to unlock the laser fence inside the room which gives access to the BFG ammo and the secret.
From here continue the mission up to the portal, when reaching the portal you will find the final codex page to the left side of it. This is also our final item of the mission and DLC.

The final boss mission doesn't contain any collectable items so that is it for this DLC, well done!

If this guide has helped you then please help me out and give it a thumbs up. Much love!

DOOM Eternal DLC: All collectables
https://youtu.be/MN4HV3aHLwo
DOOM Eternal Base game collectables:
https://youtu.be/yRLYR_jUgwA