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Doom Eternal Mars Core collectables: all secrets in the seventh mission

How to complete the challenges in mission seven

Dave Irwin avatar
Guide by Dave Irwin Former Guides Writer
Published on

I have some good news and some bad news regarding the seventh mission of Doom Eternal. The good news is that there are fewer collectables here compared to the previous mission. The bad news is that there are still 20 of them. Once you have them, the vast bulk of the collectables will be yours, so let's get into it.

Doom Eternal Mars Core collectables guide

The seventh mission of Doom Eternal has 20 collectable items. You'll also need to find the various secret encounter locations and the Slayer Key, so it's no mean feat to get everything.

As always, it's worth noting that getting to the end of the mission enables Fast Travel so you can pick up collectables that you missed. The automap also helps here and the automap is found when accessing the core from the maintenance shaft. It should be right in front of you by the turbines.

Contents

Here are the locations of the collectables hidden in the seventh mission of Doom Eternal.

Mars Core collectable locations

  • Rune #1: After going through the teleporter and killing the Baron Of Hell, go through the doors at the back for the rune.
  • Sentinel Battery #1: Walking along the outside of the base, there are two cannons firing either side. This is where you first meet a Pain Elemental in the main campaign outside of Slayer Door challenges, as well as a Doom Hunter. Go down the maintenance shaft that opens and hop across the platforms for the battery.
  • Praetor Suit point #1: In the maintenance shaft, there is a generator room with pistons that rise and fall. It’s the same location as the automap. Climb up to the top and jump to the knight hidden on the other side of the room.
  • Codex Entry #1: At the top of the generator room, go through the vents and turn left for the Codex Entry.
  • Praetor Suit point #2: After getting the BFG9000 and hopping through the teleporter, jump to the next big area. After the first major fight in this area, a hole will open up. Go down it and look to the wall that has been blown open. Jump and dash around the circumference of the building to the left to find a gap. This has the knight who has the Praetor Suit point.
  • Toy #2: Going up the lift, you'll find a Ion Catapult command panel. Use it, then go through the door behind you. It leads to the toy.
  • Rune #2: On the way to the Ion Catapult, you should find the rune on the main path.
  • Cheat Disk #1: After being yeeted into the side of a building by the Ion Catapult, proceed until you come across a path leading downstairs. Proceed onward, punching any tentacles on the way. You'll see a booster to the right. Go up it for the Cheat Disk.
  • Praetor Suit point #3: Across from the room where the Cheat Disk is, there is a room with lots of tentacle pods. Proceed through and into the side room. Climb up the boxes and find the knight.
  • Record #1: From the Suit point, swing across the monkey bars ahead, then use the booster on the floor to head backwards and into the hole in the ceiling. The record is there.
  • Toy #3: Proceed to use the monkey bars again in the room with the tentacle pods, but this time go down the hole. Proceed through the door labelled "Maintenance 02" and use the portal inside. This is in the opposite direction to the waypoint marker and the harmful electric pods. Head up the booster ahead. The toy is in this room.
  • Praetor Suit point #4: After eliminating the the Baron Of Hell by the radio spire, climb up the platforms to reach the health kit, then boost dash over to the knight.
  • Sentinel Battery #2: At the Union Airspace chimney-like thing, boost away from it using the booster, then use the monkey bar and platforms you pass on your left to make your way back. Jump to the top to pick up the battery.
  • Sentinel Crystal #1: After boosting away from the Union Airspace chimney, enter the door in front of you to find the crystal next to a control panel.
  • Empyrean Key: In the second room that's full of tentacles, head into the operations room. Use the button to raise a platform in the other room. Head back and climb up it. Punch the vent door on the right and head through for the Slayer Key. Head around to unlock the door, beat the monsters, and get the key.
  • Record #1: In the second room that's full of tentacles, head into the operations room. Use the button to raise a platform in the other room. Head back and climb up it. Punch the vent door on the left and head through for the record.
  • Toy #3: From the second tentacle room, head down the hole at the end, but turn left immediately and punch the vent. Use the booster to reach the room with the toy.
  • Sentinel Battery #3: Upon reaching the surface of Hell, drop down the ledge and turn right for the battery.
  • Codex Entry #2: Upon reaching the surface of Hell, proceed along the path and you should find the Codex Entry.
  • Praetor Suit point #5: Upon reaching the surface of Hell, head to the left and not through the punchable hole to the right. The knight is waiting for you here.

Secret encounters

  • Secret Encounter #1: It is next to Praetor Suit point #2, which is accessed after getting the BFG 9000 and hopping through the teleporter. Jump to the next big area. After the first major fight in this area, a hole will open up. Go down it and look to the wall that has been blown open. Jump and dash around the circumference of the building to the left to find a gap to find the encounter.
  • Secret Encounter #2: Use the monkey bars in the room with the tentacle pods, but go down the hole. Proceed through the door labelled "Maintenance 02" and use the portal inside. You should find it on the other side. This is in the opposite direction to the waypoint marker and the harmful electric pods.

Challenges

  • Big Ba-Da-Boom: Kill 40 demons with a very big gun. We'll give you three guesses what that very big gun is.
  • Disarmament: Destroy three arm cannon Weak Points on Mancubi. These are the arm cannons and I recommend using the Precision Bolt weapon mod for this.
  • Lock and Key: Find the Slayer Key.

You shouldn't really have too hard a time with the next mission's list of collectables. Most are on the main path and the one that's slightly better hidden is still very reachable. To make sure you don't miss out on any of them, have a look at our guides for all the other collectables in Doom Eternal:

Doom Eternal Mars Core collectbales

Doom Eternal collectables

Doom Eternal guides series

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