The Blood Swamps is the 2nd mission in Doom Eternal: The Ancient Gods Part 1 and contains 11 collectible locations (4 Codex pages, 1 Support Rune, 2 Secret Encounters, 4 Extra Lives). This walkthrough will guide you to all The Blood Swamps collectibles in Doom Eternal: The Ancient Gods Part 1.
- Codex pages: 4
- Support Runes: 1
- Secret Encounters: 2
- Extra Lives: 3
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.
Support Rune #2 – In the first large area, instead of jumping across the bars through spinning fire hazards, drop to the ground and look at the wall to find a broken section. Go through and at the end of the path you can find a Support Rune pickup.
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Codex #1 (Book of the Seraphs – Part 5) – After jumping through the fire hazards and across a gap, you will be in an area where you pick up a hazmat suit and need to go into some water. Just underneath the spot you jump into the water you can find this codex in a small inset in the wall.
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Automap Station – On the platform you climb out of the water on to, directly after the above Codex.
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Extra Life #1 – In the same area as the automap, before going up the ramps to progress you can break a wall in the corner to find this extra life.
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The next collectibles are down the left path from the central area with the sphere. You must pick these up before starting the encounter at the end of the path or you will be locked out of this area.
Extra Life #2 – Just before the second turret on the path is a platform you can stand on. Facing where the turret would be, turn 90 degrees to the right, and you can see this extra life in the wall.
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Extra Life #3 – After the room where you need to defeat a marauder to destroy a buff totem, you will drop into an area where there will be an Empowered Arachnotron. Behind where the Aracnotron is there is an area with water. Drop in to the water and dash through the cracked wall to find this extra life.
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Codex #2 (Book of the Seraphs – Part 8) – In the area with the large demon corpse where you can see it’s face and arm stretching to the right, to the right of the head there is an area of water you can dive into. Follow the path from there and jump across to where you can find this Codex Page along with a BFG ammo unit.
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Secret Encounter #1 – From the room where you fight a possessed Hell Knight before opening the large door, go to the left of the stairs leading to the switch. Follow the path down to the right, then you’ll reach a box you can punch down, which opens the gate to this secret encounter. This encounter spawns an Empowered Whiplash, two normal Whiplash, a Mancubus, and lastly a Baron of Hell. This would probably be a good encounter to use the BFG or Unmakyr on because that’s a lot to deal with within 40 seconds, and there are 4 total BFG ammo units in this level.
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Codex #3 (Book of the Seraphs – Part 6) – In the area where you jump across the two bars and then fight a Pain Elemental, you can jump across to a climbing wall, then across the area again to a ledge where you can find this Codex page.
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The next collectibles are down the right path from the central area with the sphere. You must pick these up before starting the encounter at the end of the path or you will be locked out of this area.
Codex #4 (Book of the Seraphs – Part 7) – In the area where you follow the green wolf around to progress, this codex is in an area just above one of the totems you stop at. It is recommended you wait until you progress the entire area and backtrack to pick this up.
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Secret Encounter #2 – In the same area as the above codex page, you can platform up onto the level above, then follow the path around to push a box, opening a gate. Follow the path after the gate to find this secret encounter. This secret encounter spawns an Empowered Cacodemon, a Mancubus, a Baron of Hell, and some Imps. Focus first on the Cacodemon, getting rid of it as quickly as possible, then either focus hard on the Mancubus or the Baron.
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That’s 100% of the collectibles you can find in The Blood Swamps of Doom Eternal: The Ancient Gods Part1.
Next Up: The Holt
For all other Missions, check out the complete Doom Eternal Collectibles Guide.
Snake2410 says
Beware, there is a nasty glitch with secret encounter #1. If you quit out or restart checkpoint after doing it, but before hitting the next checkpoint the game may generate an invisible wall blocking both the ledge leading to the secret, the one you drop a box from to be able to climb back up, and the top of the stairs that lead up to the giant door you need to activate a switch to the left of to open. The stairs you climb right before going to the left to find the path with the box.
This happened to me yesterday on the PS5 version and it forced me to restart the checkpoint, and many people on Steam have had it happen over the last few years. I was trying to see if I could trick the game into letting me checkpoint reset to keep the BFG ammo that I used during the secret encounter, like many of the other secret encounters allow you to do.
If you’re worried about this happening, it may be better to just finish the level skipping the encounters, and then come back using infinite ammo to easily plow through them.
Snake2410 says
I just realized I typo’ed and when it said checkpoint I meant I had to restart the entire level, checkpoint didn’t fix it because it’s one of the only secret encounters that semingly generates a full checkpoint when completed.