Unfortunately the stairs from the 2nd floor to the 3rd won't trigger (I tried twice), when I walk onto them then I'm just stuck there.
I'm saying unfortunately because otherwise the game is pretty great. Movement is definitely too slow but in the case of this game the level design is pretty tight so it's no big deal. I guess it also prevents you from running into holes ;) . It's tight and great, what I like to do is to bring the red key from the first floor to the 2nd so I can bypass part of it, I actually love that it's possible to do that. The game looks great and ambitious, one thing I really like is that the 2D potions fit perfectly inside environment. The fast combat works well and the game delivers some very good resource managment, trying to avoid some enemies instead of bumping into all of them is no luxury, I like trying to find the best route, and in the same time in practice you can't really avoid all of them which is good too. I like that getting the new spells is optional, this is more open which is good.
Sometimes you can get stuck in combat (there's no enemy, and I'm almost sure it's not only visual, you can attack but it effectively does nothing) but I think that only happens if you mash the buttons so it's far from unplayable anyway.
Overall this is a very cool game, I'll play up to the end if you ever get to fix the stairs bug.