Arc Complex is the 6th mission in Doom Eternal and contains 32 collectible locations (3 Toys, 2 Modbots, 5 Codex pages, 1 Cheat Code, 2 Runes, 3 Sentinel Batteries, 1 Sentinel Crystal, 2 Albums, 2 Secret Encounters, 5 Praetor Suit Tokens, 1 Slayer Key, 1 Slayer Gate, 1 Empyrean Key, 3 Extra Lives). This walkthrough will guide you to all Arc Complex collectibles in Doom Eternal. If you missed something you can get it via mission select.
- 3 Toys
- 2 Modbots
- 5 Codex Pages
- 1 Cheat Code
- 2 Runes
- 3 Sentinel Batteries
- 1 Sentinel Crystal
- 2 Albums
- 2 Secret Encounters
- 5 Praetor Suit Tokens
- 1 Slayer Key
- 1 Slayer Gate
- 1 Empyrean Key
- 3 Extra Lives
All collectibles in this chapter are listed in chronological order. If you miss anything you can use fast travel when it unlocks at the end of the mission to go back everywhere.
Toy #1 (Mancubus) – Near the start of the level a mancubus will break out of a shop door, the secret is in this room in the back.
Praetor Suit Token #1 – After going down a few floors, there is a token behind you after coming down some stairs, punch the glass to get it.
Modbot #1 – In the next building you’ll climb some escalators after fighting some demons, climb up to the next ledge and turn right to see the modbot.
Sentinel Battery #1 – Turn around from the previous collectible and go forwards and left up the stairs, jump across the gap here and find this on the left.
Toy #2 (Cueball) – Same as the above but on the right.
Slayer Key #1 – In the same area as the above, this time turn around and jump to a wall on the left, turn around and jump towards the key.
WARNING: The slayer key might not spawn in the mission. If it doesn’t the ONLY fix is to pause BEFORE completing the mission and choosing RESET MISSION, it does NOT spawn it via mission select.
Slayer Gate #1, Empyrean Key #1 – As usual the Slayer Gate is found in the purple circle marked on the map. This is the hardest one so far. To kill the two large demons faster, destroy the horns on their heads.
Cheat Code (IDKFA) – Once you jump across to the next building, in a hole just in front of you.
Modbot #2 – From the last collectible go up the stairs and then to the right, punch the cracked wall here leading to the modbot.
Codex #1 (The Arc – Part I) – Soon after you will be launched upwards by a blue vent in an elevator shaft and then go down a small slope and jump across to another building, look left and climb over to find a cracked wall to break, go all the way up the stairs to find the codex.
Sentinel Crystal #1 – Go back partway down the stairs and climb up instead, the crystal is around the corner (already collected but this is the location).
Extra Life #1 – In the middle of a climbing section where you must use hanging bars to swing up the buildings. Next to a voice terminal you must punch the door.
Praetor Suit Token #2 – After climbing up the buildings outside, you’ll come to a UAC hologram that’ll activate, it’s just to the left of this.
Codex #2 (Samuel Hayden) – In the combat encounter area, climb up 2 flights on stairs and exit left to find this behind a pillar ahead.
Praetor Suit Token #3 – Just across the gap from the previous codex.
Secret Encounter #1 – Right next to the above token.
The ballista is your friend here, use it to quickly kill the pain elemental and cacodemon, then finish off the arachnatron on the ground (can also use Rocket Launcher or Chaingun here).
Toy #3 (Whiplash) – Once you reach the top floor go left and left again to find this.
Extra Life #2 – In the next building, it will be to your immediate right.
Rune #1 – Same building as above, after dropping down a hole in burning corridor.
Codex #3 (The Arc – Part II) – Soon after you’ll drop down again and have a huge fight against demons, this codex is found in the back behind a desk.
Sentinel Battery #2 – After firing the east turret and going through a couple of doors you’ll see this in a room just in front of you.
Codex #4 (The Return of Dr. Samuel Hayden – Part I) – In the next room you’ll fight some demons and a pinky will come running at you, this codex is in the left corner behind a generator.
Praetor Suit Token #4 – On the right as soon as you leave the room with the previous codex.
Rune #2 – Slightly further ahead you’ll fall through the floor, the rune is just to the left.
Sentinel Battery #3 – In the 2nd room with the purple ooze, you need to swing on the bar over the fence, turnaround and dash to the platform with the battery.
Codex #5 (The Return of Dr. Samuel Hayden – Part II) – After dodging numerous electrical currents in the next few corridors you will be attacked by a lone cacodemon, to the left is a small room, hit the switch then go back down the previous corridor and enter the newly unlocked door, follow this so the end for the codex.
Extra Life #3 – To the right of the above Codex.
Album #1 (Quake II – Quad Machine) – Drop down from the above codex and find this album in the left corner of the next room behind a generator.
Secret Encounter #2 – Directly opposite of the above album.
The Balista destroyer blade mod with a freeze grenade makes quick work of this, otherwise the rocket launcher and frag grenades will do, anything that does wide area damage.
Album #2 (Quake III – Intro) – After firing the west cannon and the big fight in the garage, go left into another room to find this secret on the right.
Praetor Suit Token #5 – On the lower floor of the garage, just to the left of the exit.
That’s 100% of the collectibles you can find in Arc Complex of Doom Eternal.
Next Up: Mars Core
For all other Missions, check out the complete Doom Eternal Collectibles Guide.