EDIT 2: I finally got around to playing up to the boss and found out (surprise!) it glitches. It resets its size when it's not supposed to. Be a nice gamer and lose when you get there, ok? :) I'll fix it later...
EDIT:I messed around with the spawn rate so that the enemies spawn faster and stay faster for longer. Also, I added a "backup" for getting rid of the enemies. If an enemy just sits there spinning, it won't take forever to disappear anymore. Eventually I'll make it so that it won't do this at all, but I'm in the middle of another project right now and am too lazy to do anything major.
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.