NOTES ON THE REMASTER: I have attempted to provide a running count of all kills and pickups, including totals for health packs, chocolates, sellable items, and cash, as well as notebook entries, which are needed for some achievements/trophies. If I've missed any, I do apologize. Please let me know if you discover anything not mentioned here. These guides are based on classic tank controls, but I hope they will be useful for those using modern controls.
LEVEL 25: AQUATIC RESEARCH AREA (Remaster)
Updated: 7/19/25(†)
LEVEL MAP by VGCartography (used with permission)*
Angel of Darkness Remastered Video Walkthrough by Eldincy
Items: 3, including 1 health item
Kills: 2
Upgrades: Upper Body
Notebook Entries: none
ROOM WITH MACHINE GUNS: Now Lara is back in action. Press the button to open the airlock doors. The next area has sensor-triggered machine guns, which will kill Lara if she comes within range. So, don't climb down the ladder. Instead safety drop off the walkway to the left of the airlock. Crawl along the floor to the left. Then drop into a commando crawl (Duck + Stealth) to squeeze through the small, rectangular opening near the wall. Beyond that you can stand. Turn the valve and wait about 10 seconds for clouds of steam to fill the room. Now, as long as Lara doesn't stand directly in front of one of the guns, the sensors won't spot her, and she can move freely. (screenshots)
Climb over the stacked crates near the valve and head for the wall behind the second gun. Climb the pipes on the wall upward, right, then up again. When you reach the narrow ledge, traverse along it to the right and around the corner. Then drop onto the jutting ledge in front of the open doorway. (If you run out of strength, you can pull up onto the ledge as soon as Lara rounds the corner and then drop down near the doorway.) (screenshots)
SMALL STORAGE ROOM WITH GUN: Follow the hallway around the corner and down the steps. There's a security camera you can use to scope out the next room, but this isn't necessary. (If you try the camera, press Esc on keyboard or Roll on controller to disengage from it.) There are 2 more machine guns at the far end. To destroy the guns, draw a weapon and advance just far enough so Lara aims at the panel with the blinking light and "Flammable" sign. (You can use Photo Mode to get a better view, or just trust that Lara knows what she's doing.) Shoot this panel several times to set off an explosion that destroys the machine guns. (screenshots)
Now you can pass. Just watch out for the steam billowing from the pipes. It will kill Lara if she walks under it. Instead, stay to the left and climb over the boxes. Then approach the blue door from the side. Press the button and go through. (screenshots)
NOTE: Alternatively, you can commando crawl across the room. The guns will start firing but won't be able to hit Lara if she's hugging the floor. Crawl all the way to the far corner to the left of the door before standing up. The guns can't "see" Lara in this corner. Carefully sidestep toward the button but don't step out too far. Press the button and run through the door.
In the circular shaft beyond the machine gun room, climb the ladder, then follow the hall to the right. Continue around the corner and up the steps. The next door opens automatically and leads into the Aquatic Research area proper. (screenshots)
LARGE ROOM WITH POOL: The power is still out here, and the place appears deserted, but there are "Danger" signs everywhere. The hazard is in the water: the Leviathan, a huge, aquatic mutant. You can't kill it, but it can kill Lara with one bite. The goal is to reach the underwater exit without being devoured. (screenshots)
If you didn't unlock the "Into the Hellmouth" achievement/trophy back in the Bio-Research Facility level, you can do it now. Move down to one of the ledges just above water level. Quick-save. Then aim for the pool, start walking forward, then press Jump to swan dive. The achievement/trophy should pop when Lara hits the water. Reload or quickly swim to one of the square ledges and climb out of the pool. (screenshots)
RESTORING THE POWER (FIRST LEVER): From the entrance, follow the walkways around to the far right. Notice that this section of pool has a sturdy fence separating it from the main tank. Jump into the water and swim down through the broken observation window. Swim to the left side of the flooded room and pull the lever. This restores partial power to the area and opens a door above, on the opposite side of the big pool. (screenshots)
If Lara's air meter is still at least half full, roll, swim away from the lever, and continue through the doorway opposite. (Or, if you need air, return to the surface. Then swim back down through the broken observation window and this time go to the right.) In the flooded room beyond, swim upward then straight forward through a wide doorway with black and yellow stripes around the opening. Swim through the square hole in the ceiling and straight up the vertical shaft to the surface. Climb out of the pool. Get the small medipack (1) on the walkway to the left. Press the button to open the door. Follow the hall back to the main room. You emerge through a yellow-striped doorway with a high-voltage sign above it. The fenced-off section of the pool is just ahead. (screenshots)
RESTORING THE POWER (SECOND LEVER): Follow the walkways all the way around to the far side of the room, to the door you just opened using the lever. (It also has yellow stripes and a high-voltage sign, but the pool below is not fenced off, and the underwater viewing port is intact.) Follow the hallway to the end. Press the button to open the door and enter the steamy room beyond. On the far left, there's another security camera. If you activate it, you'll get a grainy view of a small room with a pill bug mutant. Use the switch on the right to call the lift. Enter the lift and press the button to descend. (screenshots)
As soon as the doors open, run out and shoot the pill bug mutant (1) before it can poison Lara. If it does manage to hit her with the pink toxin, use an antidote or large health pack. (screenshots)
Proceed through the door on the lower level, opposite the lift, into the underwater observation room. This one is not flooded. Use the lever at the far end to restore the power levels to 100%. Return to the previous room. Use the switch to call the lift, get in, press the button, and ride up. Exit the lift, return through the steamy room, and follow the hallway back to the main area. (screenshots)
Cutscene: A flyby drawing our attention to a lever, a switch, and a ladder. So much for exploration and puzzle-solving. ;)
THE CHUM BUCKET: If you're after the "Short Ration" achievement/trophy, you'll need to escape this area without feeding the Leviathan. However, I do recommend getting the strength upgrade and the remaining pickups before moving on. This walkthrough describes how to get 100% with or without the achievement.
Start by climbing the stairs to the catwalk above the center of the pool. At the top, turn right and approach the metal bucket. Pull it onto the square, gray pad on the floor. Press the button to move the bucket along a conveyor belt to the other end of the walkway. Move to the left side of the bucket and push it into the small room so it's underneath the trapdoor in the ceiling. Use the lever on the other side of the small room to dump some nice, juicy chum into the bucket. Now pull the full chum bucket back onto the gray pad. Lara gets an upper-body strength upgrade when you do this. (screenshots)
If you want the achievement/trophy, you don't need to bother with the chum bucket any more. Skip the next paragraph. (Or, if you don't care about 100% completion, and just want the achievement, you can head for the exit immediately. Skip down to "OPENING THE EXIT," below.)
If you don't care about achievements and want an easier time reaching the exit, press the nearby button to move the full chum bucket along the conveyor to where it was before. Then push the bucket onto the crane platform where it started. This will allow you to lower the chum into the water later on. (screenshots)
SECURITY ROOM WITH CAMERAS: Return downstairs and follow the walkways back to the other side of the room, above the fenced-off section of pool. Climb the stairs to the landing with the small boxes. Then climb the ladder into the room above. The 2 security stations on the right allow you to see a pair of levers elsewhere in the level. Lever #1 is underwater in the big pool. Lever #2 is in a side area we haven't visited yet. (Press Esc on keyboard or Roll on controller to disengage from the cameras.) Exit the security room through the door opposite the camera stations and follow the walkway down and around to a broken section. (screenshots)
CLIMBABLE PIPES: Grab onto the vertical pipe. Climb up, then right, then up some more. Grab the narrow, horizontal ledge and traverse to the left as far as you can go. Drop onto the walkway below. If you unlocked that last upgrade, Lara should have just enough strength to make it. (screenshots)
NOTE: If you're having trouble with the climb even after getting the upgrade, try climbing just as far as the horizontal ledge. Then let go and immediately press Action again to grab the horizontal pipe below. This resets Lara's grab meter. Continue with rest of the climb and you should be fine. (screenshots)
SIDE AREA WITH MUTANT SPECIMEN: Press the button to move the small platform to this side of the gap. Get on and ride across to the other side. The big doors open automatically. Press the button on the wall ahead to open the airlock door. Go into the airlock and press another button. As the airlock cycles and a new area loads, ready a weapon and take out the soldier (2) in the next room. This dimly lit room contains a preserved Leviathan specimen in a tank and various control panels, but these are just decoration. Turn around to face the door where you came in. Search the cabinets on each side of the door to find Viper and Mag clips (2-3). Then exit the way you came in. (screenshots)
If you're going for the "Short Ration" achievement/trophy, do not use the next switch. Instead, continue straight ahead, through the automatic door, back to the main room. Pick up the walkthrough below at the "SHORT RATION ACHIEVEMENT/TROPHY" section.
If you want to feed the Leviathan and make your swim to the exit easier, after exiting the airlock, turn right and go up the steps into a little control room. Use the switch there to lower the full chum bucket into the water. Return to the room with the pool and drop into the water. This should distract the Leviathan so you can swim safely. Return to the main area through the large, rectangular door. (screenshots)
NOTE: If you're having trouble holding your breath when attempting either version of the swim to the exit, and you happen to have extra respirators in your inventory, left over from the Louvre levels, you can use one here.
OPENING THE EXIT - USING THE CHUM BUCKET DISTRACTION: Turn right and drop down to the walkway below the broken ladder. (Or, just dive into the pool from above, if you prefer. This is another opportunity to get the achievement/trophy "Into the Hellmouth" if you haven't already done so. See above for swan-diving tips.) (screenshots)
Swim across the pool and pull lever #1, which is just below the entrance and power-monitoring panel. Doing so opens the first of two trapdoors on the bottom of the pool, as well as another underwater door on the opposite wall. Swim across the pool, past the trapdoor. If you need air, head for the surface. Then swim through the door below the "2" sign, directly opposite the first lever. Follow the passageway to a vertical shaft and continue upward to the surface. (screenshots)
Cutscene: Lara climbs out of the pool, changes into a wetsuit, and presses a button to raise the water level.
Surface to breathe. Then pull lever #2, which is just below the waterline in this room. This opens the second trapdoor at the bottom of the main pool. Get air again if necessary, then swim back down to the main room, through the two open trapdoors in the middle of the pool, and on to the next level.
OPENING THE EXIT - "SHORT RATION" ACHIEVEMENT/TROPHY: After exiting the side area without lowering the chum bucket, turn right and drop down to the walkway below the broken ladder. At this point, you may want to take a few minutes to lure the Leviathan into this section of the pool (i.e., the area opposite lever #1, which is just below the entrance and power-monitoring panel). To do this, drop into the water to get the mutant's attention. (Quick-save first, just in case.) Then, when it approaches, quickly climb out using the half-submerged ladder. If you pause on the ladder, with Lara's legs still in the water, the Leviathan may float up to the surface, which should keep it contained here for a little while. If this doesn't happen, don't stress. It's still possible to outswim the creature with a bit of trial and error. (screenshots)
Follow the walkways around toward the entrance. Once you're standing above lever #1, save the game in a new slot. You can quick-save periodically if things are going well, but do not overwrite the manual save until you complete the sequence. The Leviathan can one-hit Lara, even during the cutscene that plays after using the lever, so this may take several attempts. When you're ready, dive in. (screenshots)
NOTE: If you didn't unlock the "Into the Hellmouth" achievement/trophy earlier, this is your last chance. See above for swan-diving tips.
Swim down and pull lever #1 to open the first of two trapdoors on the bottom of the pool, as well as another underwater door on the opposite wall. Roll and swim across the pool, past the trapdoor. Try to stay close to the bottom, since the Leviathan is less likely to attack if you stay low. Do not surface for air. Just swim along the bottom until you reach the door below the "2" sign, directly opposite the first lever. Once you enter the passageway, the Leviathan won't pursue. Follow the passageway to a vertical shaft and continue upward to the surface. (screenshots)
Cutscene: Lara climbs out of the pool, changes into a wetsuit, and presses a button to raise the water level.
Surface to breathe. Then pull lever #2, which is just below the waterline in this room. This opens the second trapdoor at the bottom of the main pool. Get air again, quick-save, then swim back down to the main room. If the Leviathan is lurking outside, try to swim behind it, rather than in front of its mouth. Or just reload your quick-save, wait a bit, and try again. Once you exit the passageway, again stay close to the bottom as you head for the middle of the room. Swim down through the two open trapdoors. The achievement/trophy should unlock as the next level loads. (screenshots)
†UPDATE HISTORY: Updates made prior to the Tomb Raider IV-V-VI Remastered release, including credit for tips sent in by other players, are tracked in the archived classic guide.
7/19/25 - Remastered guide posted.
*NOTE ON LEVEL MAPS: VGCartography's Angel of Darkness maps follow a slightly different level-numbering convention than I do. You'll notice most of the Parisian Ghetto-adjacent areas on the same large map. Later, the elemental levels off the Hall of Seasons are included on the same map as the hub level. Visit VGCartography on DeviantArt and follow on Twitter/X and YouTube for more fantastic game maps.
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