Doom Eternal: Ancient Gods – All Codex, Rune Key & Secret Locations | The Holt

Doomguy returns to the heavenly realm of Urdak to summon the Dark Lord in the first part of this singleplayer Doom Eternal DLC. This level presents some of the most absurd challenges in the game — throwing everything at you all at the same time. You’ll have to deal with Marauders, Tyrants, and new enemies like Spirits and invincible angels that pelt with you killer attacks.

There’s a big multi-stage boss waiting for you at the end. The only saving grace is that there are checkpoints along the way, or this stage would be practically impossible. This DLC is cruel and unusual punishment, even on the ‘normal’ difficulty level. I made it through thanks to liberal use of the BFG, extra lives, and ego-boosting breathers grabbing all the collectibles (and skins) in the level.


More Ancient Gods DLC guides:

UAC Atlantica Facility Collectibles Guide | The Blood Swamps Collectibles Guide | How To Unlock Support Runes & Which To Pick First


In the Ancient Gods campaign, you’ll earn new skins for completing all of the Secret Encounters in a stage. You’ll also earn new Support Runes by completing the challenging Rune Gates.

Slayer Key: After the first big battle of the level where a Marauder and Tyrant spawn together, continue into the waterfall courtyard and punch down the tree. Climb to the top, then climb a nearby ledge — now you can backtrack toward the high ledge with this key, marked on the map.

1-Up: In the same area with the tree you have to knock down, enter the left optional path to find this 1-Up.

Secret Encounter #1: From the fallen tree, go forward and look to your right for a cracked wall in the pink-water cave.

1-Up: Climb the ledge to the left of the top of the waterfall, and follow the path left to another cracked wall.

Slayer Gate: Continue into the area filled with imps. Ahead you’ll reach an Arachnotron empowered by a Spirit. The Slayer Gate is to the right.

Map: The map is up the path from the Slayer Gate.

Look closely to spot the codex way down there.

Codex #1: After jumping on the trees and encountering the Hell Knight, you’ll reach a vast expanse ahead. Drop directly down from the ledge to find this first page.

2-Up: When you reach the floating platforms, jump to the second pair of breaking platforms — to the left there’s a cracked wall you can dash through to gain 2 lives.

BFG Ammo: In the arena with the electrified floor / pillars, hit the third button and then look on the right wall for a cracked wall. Smash through it to find this ammo.

Codex #2: To the right of the switch on the ledge facing the massive main facility of this level, right after the pillar combat area.

To open the secret encounter, shoot this target on the ceiling.

Secret Encounter #2: Found after clearing the room that ends with three Barons of Hell, the first main encounter in the center zone of the map. Found near a mission critical button.

  • To unlock the door, look at the ceiling above the button to activate the jump pad. There’s a green target — shoot it!

Codex #3: After re-activating the jump launcher, ride up to the second level of the Holt facility and enter the mission objective button room. It’s on the left.

Turn around in the room before the boss to spot this target that unlocks the codex door.

Codex #4: Hit the button on the second level, then continue to the area that splits into two combat encounters.

Codex #5: Complete the small jumping puzzle past the forking path, and find this codex in the entrance hall to the right of the BFG ammo.

  • To unlock the door, reach the lobby before the final boss of the level. Turn around and shoot the green target on the backside of the object with the pole, and the door will open.

More DOOM Eternal guides:

10 Tips & Tricks To Start Demon Slaying Strong | Beginner’s Guide | How To Unlock The Unmaykr | Secret DOOM 64 Gun Guide | Cheat Codes Collectibles List & Locations Guide | How To Farm Weapon Mastery Challenges | Best Runes To Unlock & Equip First | Easter Eggs Guide | Tie-In Novel Trash, Dopefish, Unmaker & More | How To Unlock Doom & Doom 2 Classic