Walk forward, jump into the pool and shoot the chains that attatch the raft to the bottom. Once it's raised, jump on, nut the switch.

Go forward and down the hole, forward again and use the diagonally positioned bars to reach the upper platform. Carry on to a hall full of boxes - nip through and let the Nali show you to some goodies.

Press the button, go up the lift and hit the switch on the left balcony. Drop down, hit the switch and open the door. Go to the hallway on the right, fall off the bridge and kill the beast below.

Cross the baracross the pond, jump to the button, walk to the hall and hit the button on the left. A bar will lower opposite - step on, go up to the previous room, press the button again and head down the stairs.

Go over both bridges and push the large levers; then go over to the other side and press the button in the dark wall. Go through the now-opened door behind you.

Head down the stairs, find the Super Health by leaping from the smaller blocks, then go right and right again. Press the buttons on both of the blue lights, go back, enter the alcove that's opened, press the button and go through the door.

Go through the door on the right and carry on until you enter the long room with the central tower, flick the switch on the wall and pick up the eightball launcher. Go through the doors that lead you to the pool and dive in. It's now possible to enter another hall with a pedestal on a tower - jump onto it, go through the side opening and find ammo for your eightball launcher.