Try to defeat the enemy by using spells. Don't let him touch you though. Use WASD to move and the arrows to change direction. Press space to enter infinite mode. In this mode the enemy lasts forever, and you have to try to deal as much damage as possible before they touch you. Electric Element: Does one damage, 1 second cooldown. Fire Element: Does 3 damage, 3 second cooldown. Ice Element: Will freeze the enemy, 10 second cooldown.
I used SammyCheez's tutorial since I was confused on how to make the bullets disappear at the right time, so thanks to him.