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If it's been destroyed, you'll have to walk the balance beam on the pipes to the right. Go through the airlocks, and then across the catwalk. Make your way down to the second level of the test chamber and whack your way through the boarded door while the tentacles are distracted. The tentacles will go after that noise, giving you some time to haul ass. since the tentacles are attracted to sound, make some big booms to throw them off by tossing a grenade away from you. They will hear your footsteps you if move too fast, they will hear your landings if you jump, they will hear you fire your gun or bang your crowbar. These three tentacle things don't seem to have any eyes, but they have some very acute hearing, as the scientist up a ladder on the other side of the control room will tell you. What's all this banging you hear? Listen to what this poor dying scientist has to say, then keep going. Use the switch inside to travel through to the other side. Use the switch to open the airlock, then step inside. Those small canisters you see lying around can put some hurt into an alien if you shoot them, but they can put some hurt into a walkway too, so be careful. Travel around the outside edge of the big deep pit, killing monsters along the way. Run quickly over the the slanted pipe, run up it onto the big lift, then press the button to start the long journey upwards. Go down and to the left, then jump off into the slime. Run on top of the pipes around and to the right, then jump off, over the rail, back onto solid ground. Jump out of the pipe again, and go to the left to climb up a ladder. Climb up the ladder on the other side and drop down into the big open pipe up there. Hop up on top of the now-stopped train to reach the ledge which circles around the slime pit. Olympic hopefuls: practice your Greg Louganis impression by seeing how far you can launch into the slime pit.
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