The Blood Swamps

The Blood Swamps is the second level of The Ancient Gods, Part One, the first expansion for Doom Eternal. The level is set in the Blood Swamps, a fetid swampland in the bowels of Hell, above which is a location called Ingmore's Sanctum where the life sphere of The Father is stored. The Seraphim has tasked the Doom Slayer with recovering this sphere as he believes only the Father can prevent his Transfiguration and restore Urdak; however, the Slayer intends to destroy the life sphere instead. To reach the Sanctum, the Slayer must complete a rite known as the Trial of Maligog.

"With Samuel Hayden revealed as the mysterious Seraphim, the Slayer journeys into Hell once more to seek the resting place of the Father's essence. Only the creator of all things can save Urdak and repel the hordes of Hell. The mire of the Blood Swamps is littered with the corpses of countless dead who have tried, and failed, to reach the peaks of Ingmore's Sanctum where the Father's life sphere lies."

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Lore
The Blood Swamps extend for miles across Hell, ridden with disease and plagued by acid rain. In the center of the swampland, the Ingmore's Sanctum rises into the clouds as a solitary remnant of Hell's ancient past as the holy realm of Jekkad. From the sanctum, the Father once made decrees of wisdom and oversaw his many works. It is there, in the mausoleum of gods, that his life sphere is stored. The sanctity of the spheres is protected by an ancient ritual known as the Trial of Maligog.

During the Unholy Crusades, lone Night Sentinel warriors sometimes wandered into the swamps attempting to overcome the Trial and reach the rumored resting place of the Father. Argenta legends state that their spirits are bound eternally to the grounds of the Trial, waiting to witness it finally overcome.

Objectives

 * Destroy the Father's life sphere
 * Complete the trials (0/2)

Essentials
Head forward to find some zombies by yellow egg-like growths; these growths will explode and release toxic gas if you get close to them, so use caution. Jump across a pit and dispose of a mancubus then look past it to see some platforms over a water pool; you may want to enter the pool and dispatch the demons from there first, as there is a giant tentacle below the surface and you want some room to dodge its attacks. After getting rid of the tentacle, go back up to the platforms and use them to reach a ledge on the other side of the pool, then head down the steps to find some more growths; dispatch the demons in this area, then get ready to deal with a marauder that appears near a large gate. Head up some steps to two gas jets and kill a Hell knight that jumps up, then time your run past the jets and some swinging chains to reach a ledge where some imps will appear. Jump across to the platform on the other side then drop down to collect a rad suit guarded by a cyber-mancubus; dive into the toxic water pool and follow a submerged tunnel until you can surface, where you will find the automap station.

Climb up to the next floor and kill a baron of Hell that emerges from behind the rocks in front of you, then head up a ramp and climb past some growths until you swing off a monkey bar to a climbable wall. Look right to see a stone platform and jump to it, where you will find a skull switch that opens the portcullis in front of you as well as opening a gate below. Kill the mancubus that jumps up then drop to the ground and head through the gate you just opened to reach the arena for the Trial of Maligog. The key to Ingmore's Sanctum is protected by a blue forcefield; to reach it you will have to collect two halves of a shield from the castles on either side of the Blood Swamps, which may be collected them in either order.

Betruger Castle
Take the left-hand path from the Trial of Maligog and head up the steps past some imps, dispose of a whiplash then jump over the pit and continue following the path until you reach a turret stationed by a second pit. Use a monkey bar to swing across the pit, destroy a second turret waiting below then jump to the top of the waterfall and slide down the slope behind it. You will be informed that a buff totem is in the area; rush straight past the approaching demons and follow a trail of armor shards up some steps then head forward until you drop into a chamber containing the totem, which is inside a cage. Defeat a marauder that comes through a red slipgate (which will also be empowered by the totem) to open the cage so you can destroy the totem, then climb onto a platform in one corner of the chamber and leap along two climbable walls to reach a skull switch that will reveal a punchable block outside. When you try to go outside you will be confronted by a Hell knight that is possessed by a spirit; possessed enemies are faster, take much less damage and cannot be stunned so you will have a tough fight on your hands. Once the knight is killed, destroy the released spirit using the plasma rifle's Microwave Beam mod before it takes another host.

Head round to the punchable block you released earlier and knock it into an alcove, then climb up the block and head down the steps to a swamp pool - there is heavy fog in this area which will restrict your vision, so watch out for surprise attacks. Destroy the turrets and arachnotron overlooking the area then climb up to a platform that has a column with another punchable block embedded in it, then jump up to a ledge with two spinning chains. Defeat the approaching Hell knight and imps then punch the green-cracked wall on your left to collapse the bridge; slay a giant tentacle and Doom hunter that appear below, then go back to the punchable block and strike it so it crosses the collapsed bridge and comes to rest under a climbable wall. Time your climb to get past two fireball launchers, then follow the path to a monkey bar leading to a gate with a green crack in it. Punch through the gate and head down the steps to enter a second area with heavy fog.

Slowly push your way through the fog until you see some mecha zombies ahead, which will shortly be joined by a possessed arachnotron followed by two spectres and a Doom hunter. Once all significant opposition has been cleared (the zombies will die automatically), continue through the fog until you reach dry land then climb up past some growths to a punch switch that will temporarily open a gate ahead; after the cutscene, strike the switch a second time to open the gate again, then use the monkey bars to swing past it and reach another climbable wall. Go up to an area with zombies and press the skull switch next to the green block receptacle, which will activate a launcher; use it to catapult yourself over the heavy fog area then head down the steps and run past some growths into a pool containing whiplash spectres and a tyrant. Head up a staircase past some growths and kill a Hell knight and dread knight at the top, then go up another flight of steps to a skull switch that will unlock a large gate in front of you. Go through the gate to reach the underbelly of Betruger Castle.

You will see a cutscene of the path you have to follow; take as much in as possible because the next section is timed. Go down the steps and turn left to see a punch switch; striking it lowers a barrier around the climbable column in the middle of the room but also causes fog to start rising, and if you fall into the fog or let it catch you then you will have to start this section again. Leap to the column and head left, then look round to jump to a second climbable wall behind you; go up it and jump over some fireball launchers to a platform above, turn left and swing over a monkey bar then shoot the green switch above you in mid-air to reveal another climbable wall. Jump left from this wall and swing off another monkey bar to a ledge, then turn left to see a rotating platform with flame jets; go to this platform and immediately look right to shoot another switch that will open a gate beneath it. Go through this gate and follow the tunnel past some more fireball launchers, then use the launcher above them to propel yourself to a gate leading back outside where you will be safe.

Jump over the pit on your right to dispatch some zombies and a pinky, then look ahead to see two rotating monkey bars; you must time your leap between the bars to reach a climbable wall on your left, which you can follow past a flame jet to find some more zombies and a pain elemental. Head up the three circular platforms to a launcher which will propel you to a climbable wall, then go up it to reach the top of Betruger Castle; as soon as you reach it, turn left to see a block with a green pressure pad that you can step on to begin the first combat trial. A buff totem will immediately spawn above a launcher at the opposite end of the arena; destroy it then deal with the revenants, Hell knights and carcasses that teleport in to spawn a second totem by the upper-most blue portal. With the second totem destroyed, dispose of the two tyrants followed by four barons that spawn in pairs (a possessed demon spawns alongside the final pair so keep your eyes open for it). Once all the demons are killed, a Night Sentinel spirit will appear by the arena entrance holding a shield half. After taking it, you will automatically be returned to the Trial of Maligog.

Ishii Castle
Take the right-hand path from the Trial of Maligog and head up the steps to a revenant, then continue on to face a whiplash and a cacodemon. Continue climbing to the top platform then turn around to see a ledge with an armor pickup on it that you need to jump to. Use caution throughout the next region as the green mist in this area inflicts continuous damage while you stand in it; there is a spirit wolf on the path ahead that will protect you from the mist as long as you stay close to it. Along the way are a series of braziers that the wolf will light to create circular safe zones - you must clear the demons from each safe zone before the wolf will proceed. The safe zones contain (in order) blaster soldiers and a cyber-mancubus, imps and a turret followed by whiplashes and Hell knights, dread knights with a cacodemon and mancubus, shield soldiers followed by a spectre and baron, and finally a turret and a marauder. Clearing the last safe zone will dissipate the mist, allowing you to explore the area freely.

Climb up the nearby curved staircase to a skull switch that will unlock a large gate in front of you, then enter that gate to enter the underbelly of Ishii Castle. You will see a cutscene of the path you have to follow; take as much in as possible because the next section is timed. Turn left to see a punch switch; striking it lowers a barrier around the climbable column in the middle of the room but also causes fog to start rising, and if you fall into the fog or let it catch you then you will have to start this section again. Leap to the climbable column and head all the way right to jump to a platform with a growth, then look left to a launcher and use it to get to a monkey bar; swing off the monkey bar and shoot the green switch above you in mid-air to reveal another climbable wall, then turn left to jump to a broken bridge where fireball launchers will shoot at you. Turn left at the launchers to jump to a rotating platform with flame jets, then head round the column to a monkey bar that leads to safety. Once you get outside you will see three metal platforms guarded by spinning chains - you must jump up the platforms quickly before they fall away, then swing off a rotating monkey bar to a fourth platform from where you can jump to the next safe point.

Swing off the monkey bar in front of you (the water below contains tentacles) to a platform with imps and a turret, which will shortly be joined by a possessed Hell knight; after killing them, go up to the turret ledge and use the launcher here to reach the top of Ishii Castle then step on the green pad in front of you to begin the combat trial. There will be some mancubi followed by barons, and once they are dead you will face revenants followed by arachnotrons - one of the arachnotrons is possessed so stay on the move to avoid its plasma cannon. After disposing of the arachnotrons an arch-vile will spawn at the back of the arena, followed by a Doom hunter and a second arch-vile that spawns near the middle of the arena. Once all the demons are slain, go to the Night Sentinel spirit that appears in the middle of the arena to collect a shield half; you will then be automatically returned to the Trial of Maligog.

Trial of Maligog
After returning to the Trial of Maligog with both shield halves, the boss encounter will begin. The trial consists of a flying metal block containing an eye; the block will open periodically and the eye will shoot red projectiles that anticipate where you are moving to and will slow you down if they hit you. You must shoot the eye when it is exposed to damage and ultimately stun it; once the eye is stunned the block will drop to the ground and you can punch it into the blue forcefield to destroy it. Hell knights will also enter the arena to harry you, so stay on the move to avoid their punches.

Once the first block is destroyed, the second block will activate and pinkies will start entering the arena. After defeating both blocks individually, they will respawn and you will have to fight both of them together; focus on one at a time if possible, but watch your surroundings as two Hell knights will now enter the arena along with the pinky. Once the final block is punched into the forcefield it will dissipate and all remaining demons will be destroyed; interact with the panel in the middle of the arena to finish the level.

Secret encounters

 * 1) On the path to Betruger Castle you will pass a gore nest behind a metal barrier. When you reach the gate to Betruger Castle, head away from that gate to find a path leading to a cracked green wall; behind this wall is a punchable block that can be pushed onto a green receptacle which will open the barrier. You will have 40 seconds to kill a baron, a mancubus, some whiplashes and some imps.
 * 2) After dissipating the mist on the path to Ishii Castle, look round for a trail of armor shards leading to a platform in a swamp pool. Head straight forward and you will find monkey bars leading to a climbable wall; head up the wall and follow the path until you get to a punchable block, strike it then continue on to a launcher that will propel you up to a gore nest. You will have 40 seconds to kill a mancubus, a baron, a cacodemon and an imp.

Completing both secret encounters will unlock the "Wetland Warrior" Slayer skin.

Special items

 * Three extra lives
 * After defeating the first baron, look for a cracked gate in one corner of that area with a 1UP behind it.
 * On the path to Betruger Castle is a pit with turrets on either side. From the second turret, look across the pit to a waterfall then look down to see a cave opening behind it holding a 1UP.
 * On the path to Betruger Castle you will enter an area with heavy fog. Climb up to the platform with the punchable block and enter the toxic water pool next to it to find a cracked wall; dashing through the wall will drain the water and reveal a 1UP.
 * One soulsphere
 * In the arena at the top of Betruger Castle, a soulsphere sits on a platform by the uppermost blue portal.
 * Three spirit armors
 * On the path to Betruger Castle, after reaching the top of the first heavy fog area you will reach a gate with a green crack in it. Turn away from this gate to see spirit armor behind a stone block.
 * On the path to Betruger Castle, after swinging across three monkey bars past a gate to a climbable wall, turn round at the top of the wall to see a cracked stone behind you with a spirit armor behind it.
 * After dissipating the mist on the path to Ishii Castle, you will see a spirit armor on top of a tall pillar in a swamp pool. You can reach this pickup by using a monkey bar to swing across to some stepped platforms.
 * Four Argent cells
 * After clearing the swamp pool containing the whiplash spectres and tyrant, search the water on the left side of the Titan corpse for an area where you can submerge. Follow the underwater tunnel until you can surface, then head past a Hell knight and mancubus to find the Argent cell along with a Codex page.
 * As soon as you get through the timed section of Betruger Castle, turn left to see a cracked door with an Argent cell behind it.
 * In the arena at the top of Betruger Castle.
 * In the arena at the top of Ishii Castle.

Collectibles

 * Four Codex pages
 * "Book of the Seraphs - Part V" - below the surface of the first toxic water pool.
 * "Book of the Seraphs - Part VI" - next to the first Argent cell
 * "Book of the Seraphs - Part VII" - after dissipating the mist on the path to Ishii Castle, go back to the second brazier. Some steps here lead up to the page.
 * "Book of the Seraphs - Part VIII" - just before reaching the top of Betruger Castle you will face some zombies and a pain elemental. Jump to the climbable wall behind the elemental and go up it to reach a broken bridge; the page is on the other side of this bridge.
 * One support rune
 * After defeating the first marauder, go up some steps to two gas jets where a Hell knight will jump up. Drop off the edge that the knight jumped on to find a cracked wall; the path behind it leads to the support runestone.

Trivia

 * The two final trial arenas on either side of the level have names on the Fast Travel menu which are references to characters from Doom 3:
 * The structure at the end of the left half is called Betruger Castle, a reference to Malcolm Betruger.
 * The structure at the end of the right half is called Ishii Castle, a reference to Jonathan Ishii.
 * Codex entries from Nekravol state that humans considered unfit for the soul-extraction process are discarded to the Blood Swamps.