Overall the game is pretty good! The presentation is great, the gameplay takes some time to experiment and understand, but once you know what's what, even a 3-monster room isn't that bad. I find myself having a couple of favorite potions to make (*cough* invisibility and strength *cough*). But hey, blindly drinking a new potion is also great! >:D
I find it enjoyable, but in hindsight I think there's a particular case when it felt frustrating. It was the first room of the first crypt after the tutorial. A couple times I had to start in a room of 2 monsters, maybe even 3? It felt frustrating taking many turns to defeat an enemy using rocks, and I would end up dying soon after. Even if I managed to kill one enemy, I wouldn't loot them immediately and instead try to kill the other enemy(s) even though it felt impossible. But then because of that I had to retry in another new crypt when I die, often with less resources. The thing is, I feel reluctant to try a new potion mid-battle because I might be spending a turn better spent on throwing rocks, and the first room being a monster room was not helping that reluctance. In a room without monster, though, I don't feel reluctant trying out new potions.
These might be edge cases, but because it happened on my first couple playthroughs it felt kinda rough.