This was a great idea and I could totally see it being expanded into a larger game with a story, equipment that affects the die rolls, special abilities, etc. Your menu system worked well and wasn't clunky and the overall game was really clean! Also I saw you say this was your first time with pixel art, with that in mind, this looked really good!
The only downside is that the success of the player is based entirely on chance (which I suppose is part of the theme lol). I felt like to do well I didn't need strategy as much as just plain luck, which doesn't make as good of gameplay. I wouldn't have minded some sort of puzzle mode where the dice rolls are predetermined and you have to figure out the perfect way to complete the dungeon.
In the end, I think this game was a great idea and a fun result from the game jam. Also the dungeon generator was a nice addition and had some pretty fun dungeons!