Nice game! I really like how you learn new movement and attack spells and those rotate during combat, it makes it feel really good to plan out your turns.
I felt like healing potions must be really rare, I got low on health and prioritized getting to crates to get health, but I mostly just unlocked new movement and attacks - but also getting health potions when you are full on health feels pretty bad. Maybe the drop chances could change based on player health? More likely to get movement and attacks when you're higher, and potions when you're lower? Something like that to keep the player going might be cool!
I really enjoyed my time playing it, it was a lot of fun! Really nice work on your game!