Defend earth from gaseous beasts! Rage your way through 21 levels of non-stop action! Be sure to stick around at the end for some cinematic goodies. Also, there’s an unlockable Hard Mode if you beat the game. I finished it, so YES, it is possible!
WASD or ARROWS to move. MOUSE to aim and shoot. M will mute the sounds, but you’re crazy if you do. (Yeah, I’m a DnB fan…)