Enemies^2

-> Kill one enemy = 1 bullet + 2 enemies

This game has issues!!
-> The game will currently spawn too many bullets in a to ineffective way at one point and probably kill your computer. I'll post a version update after the voting with object pooling which will hopefully eliminate the issue.
-> To get a proper restart you need to refresh the page as the game does not reset bullet speed/spawn values jackshit on [R]estart.