Thanks for playing! I'm glad you liked the tree art. Indeed there are no invincibility frames, I never even considered that something like this may be necessary but I never really spawned more than 1 demon at a time. I assume you were going around collecting them? I can see how it may become a problem then as 1 hit could be game over.
Different attack types sounds great! I was actually considering adding a shop for the gold where you could purchase different scythes, which would have different properties (e.g. slower attack but more pushback and with stun). But I ran out of time.
What other kind of monster variations are you thinking?