Chasm: The Rift

IMO, this is the easiest boss. When you enter the room, there will be three crosses on the west, north, and east walls. Simply run to the west cross first, then the east cross, then finally the north cross (run into them to open, just like all the doors). If you mess up, it doesn’t reset the order, just tells you to try a different one. Once all three crosses are activated, a beam of light will enter the room. Just guide the boss into the beam of light and he’ll blow up into a bunch of chunks after a few seconds. He may shoot a few bats at you, but they’re easily dispatched with any gun, even the starting rifle. No worrying about some invisible force killing you like the Sphinx.