Great art and a fun concept. The huge UI gets kind of funny, which is great for the idea of the game. It felt like the skeletons started attacking a little too quickly after getting to you, perhaps? It felt like before the first attack's upgrade, hitting a skeleton with that without getting hit yourself is near impossible. The ranged attack felt very situational given how long it takes to charge -- basically only useful in situations where the skellies are stuck behind something. The time slow move on the other hand seems way too strong. Especially since you can cast it again before the first one runs out, and thus just have an infinite immortality, since no one can get to you.
Anyway, interesting idea and nice presentation. Good work on this!