The game looks promising, but I encountered an unavoidable game-breaking bug that made me lose a lot of progress twice in a row.
Long story short: If you try to leave the Underground Dungeon, the game will get stuck (in version 1.0.1).
When I took the exit on Underground Dungeon floor B7, it seems I stayed on the same map (now labeled as Underground Dungeon B0 instead of B7), only that everything was dark (except for the map, menu and directional movement symbols). I could even open the menu and try to take the exit again, but nothing else. What's even worse: I replayed until that point, because I thought at least the Escape Stones would work, but using an Escape Stone triggers the same bug (I tried to use them on B7 and B6 - the result was the same).
So please make sure that Escape Stones and all dungeon exits work properly, and while you're at it, an additional auto-save when descending to a dungeon's final floor would be greatly appreciated.
I know that the game is meant to be a "rogue-like", but serious bugs as the aforementioned ones are the reason why I prefer being able to save anywhere.