In the final level you start in a room with all the weopons around you then u get in the teleporter and go to the big room. click on the walls with symbols on them to lower them so you can get to the top then u flip the switch and there is a big piller in the acid that comes down when you click on it then get on it pull out the rockent launche and shoot a rocket in its brain which is the rectangular shaped thing on its head. shoot it about 3 to 5 times and it should die but you have to time the shot as the elevator goes up. good luck

extremely hard even with some cheats what u need is skill