Congrats on finishing your jam game!
I like your dungeon crawler take on the theme, completely dropping the randomness (and associated pitfalls) in favor of a more straightforward approach. The first level or two are pretty fun as you blast through skeletons. However, the rest of the game just feels like it's more of the same. I eventually just skipped enemies and gunned straight for the keys because they just weren't interesting. There was no incentive to destroy them and no drawback for ignoring them. When playtesting, try to look for the fun and how you can use that to create situations where the player wants to smash the skeletons.
For game jams - less is usually more. I think your levels would be more engaging if they didn't seem to repeat themselves in structure. Even having just 3 or 4 levels and introducing a new element in each one would help a lot of players through the entire experience. Short jam games are more likely to get feedback on the whole thing. Long jam games less so.
Overall, I'm happy with the time I spent with this game. The opening cutscene was very amusing - I would never think to spend time on cinematics for a jam, but I think it worked here. It gave your main character a little more personality.
Keep makings games!