Great project!! I'm not familiar with the engine, but it looks and feels exactly like a gameboy game! It even freezes when there's too much stuff on the screen :D
A few things to mention:
Like other people said, killing a witch is just egh. Consider making her health 1/3 of what she has now.
One time on the bossfight a snail telefragged me (spawned inside the player character and killed him). Not too big of a deal, but almost ruined my playthrough.
Also not too big of a deal, but... Why snails? :D