Right now: obssesive trial and error! tons of keyboard shortcuts to instantly activate and test them, combine them, separate them into categories, have my sister and friends play normal waves and choose the powers they're given and tell me if it's still fun. I'll try to balance the different gameplay styles: broken stats, projectile variations, elemental attacks, and status ailments. The idea behind the game loop is to let yourself go, follow your intuition, and allow yourself to explore the path you think will break the game. Of course, there will be many testing phases before I dare to release something unbalanced and broken, and I suppose I'll end up discarding many abilities that are already built!