Merely O.K.
The thing that bugs me most about this game is the rocket launcher. Sure, plenty games have it, but it gets pretty nerve-grinding to die by being blown up for the umpteenth time by aliens who outnumber you. It really makes every other weapon completely obsolete besides the sticky launcher. There is no way in hell to avoid it other than by luck and gravity, and really cuts short on the game's potential. Crouching does absolutely nothing useful other than make you a sitting duck. This game is also very, VERY, DANGEROUSLY close to Unreal Flash, with the exception of jump boosts and less weapons (this includes secondary fire). The friendly AI just make me want to kill them, too. They sometimes do NOTHING USEFUL except run in circles, literally. The Human boss is laughably easy. All you have to do is wait for the invincible and shoot him up, then retreat while he takes his toxic bath. This was a simple timekiller, and that's about it.