A lot of cool things here (as mentioned by others). I hope you develop this further.

The procedural generation and inputting your own seed add some lasting appeal here, but the gameplay itself gets repetitive after a while. There's no real need to fight the skeletons (unless they're stuck in a hallway) and barely any challenge as a result, which is something it needs. I assume there's no endpoint to the game (I got to level 12 before I decided to stop), so if the player is never at a risk of dying, there's not much to keep them engaged. There's potential here that hasn't yet been reached.

this is a decent start, but could use a bit more to it. The movement as is gets s little draining as you have to constantly mash the button. Otherwise you could probably expand this if you wanted to. Especially if the enemies could damage you. All around great start to a game, just needs a bit more to it. 

I like the minimal style on the art and you incorporated theme nicely with the animals. I would say it be ideal if we can hold the direction key to move and if the red enemies attacks us. There's not much context as too why there's a bunch of animals that need gathering in a dungeon, but it does keep me occupied a bit.