You will start of in the Submarine you were aboard at the end of Death Row. However during your journey the Aliens have destroyed the submarine and it's now sinking. The Cabin you're in is filling up with water; to get out of here you need to submerge. You will see a puzzle on the wall with switches. You will need to flip the top and bottom switch to unlock a door in the sub. You will hear a click - and if you turn around, you will see a door opening with the way out.
You will end up in a large area underwater. You don't really need to explore here at all but you can if you like for items that could be useful for instance behind some seaweed you will see Scuba Gear, etc. Whatever your course of action your next move will be to go to the surface. You will see a large building next to the water and a couple of turrets shooting you. If you have an RPG you may as well dispose of them. Whether you've neutralized the turrets or not; you won't be able to access the building because it requires an access card. You'll want to turn around, and go up into a hole in the wall near the water. Follow that path, until you come out on top and you can see out on top of the wreckage of your submarine. From here you can grab the blue access card; beware two additional turrets will emerge either side of you and start shooting as soon as you collect the card.
Proceed to the entrance of the building. As you come near the building, some assault troopers will be revealed in an opening window. You can shoot them if you wish, but you will need your rocket launcher, so don't waste too much ammo on them. (Assuming you didn't go up to the building yet). Once you unlock the door you'll encounter a few assault troopers as you go down the corridor; kill them.Behind them is a door behind two laser trip bombs; that door is locked so there's no sense in trying to go there anyway but there is Chaingun Cannon ammo if you need it; you can either get that now by destroying the laser trip bombs or wait till you get to the other side of the door and unlock it later on without having to destroy the laser trip bombs.
Anyway you'll want to take the red door with the sign that says hard hat area. If you go in here, it will reveal a large room with a conveyor belt system and an operational crane. If you look up towards the ceiling you'll see a Laser Tripbomb that could prove to be a problem for you when you travel on the crane so you can destroy that now if you want but you will have to use the RPG as it's too high up for Pipebombs to be of any use. Usually a canister being carried over by the crane will cause it to detonate so you probably won't need to destroy it yourself but the alternative of destroying it yourself is available just in case.
You can look around the area and dispose of any enemies you find but your next move will be to go on the conveyor belt. Stand on the yellow and black square and the crane will lift you up.After the crane picks you up, it will drop you off in a ledge halfway up the wall. There is another small conveyor on here where you basically need to repeat the same procedure. After being picked up by this second crane, you will get taken through the area where the laser tripbomb was earlier. If you didn't take it out it could take a lot of your health, however don't worry if it's still there just wait your turn and let the crane take one of the canisters across and it will cause the laser trip bomb to detonate and the canister will be destroyed too. When you are dropped off, you are dropped onto a moving conveyor again. You don't want to follow this just yet, you will want to turn around and take out a glass window, kill a pig cop open a red slot and get the Red Access card. In addition you will also see the other side of the door that was locked earlier, you can unlock that door and grab the chaingun ammo if you haven't already;you can also follow the corridor to the Red Door you went through earlier to get back to the conveyor room; though if you haven't destroyed the laser trip bombs blocking the way you will have to do so now or if you like you can follow the conveyor belt again to get other items and health; you'll end up in the large conveyor room again if you follow the conveyor belt the whole way. Whatever road you take to return to the Conveyor room if you haven't already made it over to the nearby room where the red access card is used, as soon as you go into the room you will trigger three pig cops that will come from behind and start shooting you. Take them out before using the red access card, as it will make a later part of the level somewhat easier; if you look around the room you will also notice a large door that isn't open yet. When you use the red access card, the card slot will drop, and you will get shot with a shrink ray. The reason is you get shrunk, and you have to make your way through small passages on the floor into another room. There is a small maze in the floor passages however. One rule about the shrunk passages; don't waste too much time or you'll expand in the passage and die. Anyway, when you're first shrunk you will want to take the right hand opening. Once in there, there's only one choice of turns to take (it is a simple maze), but go right , and follow the path until you come out in an open room. Don't take a left at the choice, that's the wrong way.
When you come out into the room, you will see a trooper on the far end, and you will still be shunk. Don't go over to the side of the room where the trooper is, you will get stepped on and killed. Stay on the far side of the room and avoid the trooper if necessary. When you expand again, you will need to shoot the trooper. From that point, there is a switch on the wall that says "Emergency Lock". Flip that. You will then need to go stand in front of the other shrinker ray in this room to get back out.
Go back the way you came. You should now be back in the area where you inserted the red access card and assuming you disposed of the pig cops you won't have to worry about being stepped on from here. To the right of the room you will now see that the large door is now open. When you expand again go through the door. You will see a large body of water; it's time for more underwater action. You'll spend quite a bit of time underwater from this point on and you'll soon see why many consider underwater the octabrains natural habitat.
Once underwater, you will come into a submerged room with a broken out window. You will need to exit the room (still underwater) to progress. When you do so, you will want to keep an eye out for several mines scattered in this area. They're not always easy to see, so keep an eye out. It's also easy to get confused under here, so you will want to stick to the path. When you exit the first room, stay right, you will pass a closed door, and then come to a similar looking room to the one you are currently in which is why it can be considered confusing but one difference is this room has a switch to the right of the window press it and this will raise the water level in front of you, and allow you to progress into another area in the level. Exit the room, and surface in the water. When you surface, there will be several aliens you will need to get rid of, as they're in your path. Once you've done that, you will need to climb up a rock face, and jump over to the other side.
Once you've made the jump, there are a few assault troopers (and maybe an Octabrain) guarding the area where you need to go, so take them down. Once you've done that, you will make your way into a small room with a couple of switches. You will want to flip the switch with an "02" on top of it. Don't flip the switch on the red pillar, it will lower the water level again. Probably best to leave it alone incase you want to come back up . The "02" switch will open a previously closed door at the bottom of the underwater area that was closed when you first went past it. Going in this door will reveal another control room guarded by a couple of Octabrains. You will see another switch in the control room pushing it will open two large doors along with some explosions and more octabrains for you to contend with.
Anyway once you're ready to proceed behind the doors you will see two large gears; don't go through them until you see a grey or blue area; that's the moment when you should swim through otherwise you'll only be squished. Once you're through a couple of Octabrains will be in the way kill them and then swim to the surface. You will be in a small room with a couple of troopers. Kill them. You can explore the room for items and when you're ready go down the waterslide. At the end of the waterslide you will end up in a very large room. Several Octabrains are in the area; kill everything in sight because you don't want any ambushes when you go into that control room since it's quite easy for enemies to sneak up if you don't take care of them beforehand.
The room with the red lighting that you saw on the way down is where you will need to go. This is the control room; Inside this room is a switch you will need to flip. Flipping this switch opens a door in one of the upper walls of the level which will reveal a button that will be needed for a puzzle you'll be doing soon. (Depending on your Skill level an Octabrain might emerge from behind the wall)
After flipping the switch you will have to perform one of the trickier moves of this level. You will see two large ramps of water running into the large pool of water at the bottom. There is one that you can go up and get on a ledge on the right. You will want to go up that ramp, and get on the ledge. You will see a couple of black pillars and a red button off to your right. You will need to get onto the first black pillar in front of you, then turn and flip the switch by shooting it preferably with the Pistol as it's a very accurate weapon and is ideal for hitting smaller targets over longer distances. This will start the two pillars moving towards each other. They will meet in the middle of the room for a fraction of a second, at which point you need to move onto the other one. When they return to their sides of the room, you will be delivered to the other side. It's quite easy to fall off on the pillar exchange. If you do, just get back up there and try again. Be sure to save it just before you attempt this because it could waste a lot of ammo depending on how many times you fall and if you run out you will be stuck there unable to go any further and you will need to reload it, so having a save just before doing the Puzzle can save time.
Once you're across you will have to fight a couple of Octabrains in close quarters, you will then come to a small room with a slime river beside it. Get on the Slime River, kill or run past any Octabrains you encounter and collect whatever goodies you see en route. It's plain sailing from here; just follow the river which will take you to the Exit that takes you to The Abyss. Alternatively if you want to do the Secret Level when you're on the river you'll notice before the exit at the end of the level some of the walls are lit up; one of the walls on your left has a crack on it, blast it, go through the hole in the wall and you'll end up in a small room; towards the back of the room you will find the Secret Exit that will take you to Launch Facility.
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Other features Edit
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Level contents Edit
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