Great game, after my initial playthrough I did a challenge to see how far you can get with only two shop items at a time and the answer seems to be 31/36 gems.
Aside from that, I do have some bugs to report (related to the ice boss), one in particular was very nasty:
- At one point, walking out of the room during his fist attack caused the fist to get stuck at its position when re-entering the room. This persisted until quitting and reloading the game.
- I also had the game crash once while fighting him, I didn't take a screenshot but I believe the error message was identical to the one in this steam post: https://steamcommunity.com/app/1459540/discussions/0/3272436223676977792/
From what I remember, the fist visibly flew upwards off-screen right before the crash happened. I also had to start a new save file after the crash as, on reload, my collectible counters became mismatched with the collection states of the actual items.