It's an FPS flash game where you kill cartoony aliens with guns that progressively get better (i.e. pistol, SMG, rifle, etc.). Aliens would either come in larger numbers or be special (i.e. ninja, invisible, metal, etc).
I remember playing it on Albinoblacksheep specifically, but it's no longer there. It's very similar to a game called "Insectonator" on Apknite, but it isn't that game. I'm sure most people remember playing this game at one point, as it was quite popular, but I just can't remember for the life of me.