NOTE: I've changed this a number of times since it was first submitted. As of now, I'm pretty sure it works the way I initially intended. As such, you should definitely play this again if you played it before this edit.
Avoid the various shapes while your pulse charges. Controls are in the instructions section in the game, but because I know no one ever reads that:
Arrow keys - move
Space - pulse
There are 6 different kinds of enemies. The last one can't die, so you just have to stay alive as long as possible.
Main music is Purkkaleiri (bom antiskarp) by Texas Faggot. Boss music is Du Hast by Rammstein.