Video games make a lot of assumptions about aliens, mainly that they're going to be two-dimensional and prone to shooting at stuff. It's an unfair stereotype, if you ask me, but also makes for a better game. That's very much the case in Super Crossfire which packs a ton of alien-blasting action. Yay for stereotypes.
This game includes 150 waves of glowing alien craft with another 150 that can be unlocked later.