The graphics look simple, but nice. I like it.

The screen effect every time an enemy dies felt too much for me... I was playing by closing my eyes and it still hurts sometimes.

I think it would make more sense to me if the colors of the enemies represented how much life they had.

And I missed the auto-atk by holding the atk button, and a bigger enemy to change things a little bit some times.

Overall it was interesting and a little fun.