Funny, this is the second game I played today with this concept, and while the other one felt balanced way on the easy side, this one felt almost unfairly hard in the beginning. Then on my third run I beat him easily and everyone had a good time! (well, expect for Belmont himself, maybe)
Since increasing minion stats also increases the amount of mana they cost, I feel like mana upgrades are a bit overpowered? On my winning run, I went for an almost exclusive mana run and just spammed as many slimes as I could. I also wasn’t quite sure if there was a difference between slimes and bats, could have maybe been made a little clearer.
Lovely spritework! The game looks really good.