Cute and nice game. I really like the cover image. I must try few time to understand how upgrade working and I like this mechanic (+/- hp) I think I found a bug. When I have blue ball and make 2/3 upgrades of projectile, my ball disappear and hero not shoot, so I was fast lost after it :c Also I am forgot. It would be cool to have some music and sounds when you kill slimes :D