Nice concept! I do like your idea of mixing a cave exploration game like Terrira with Bomber-man esc type of bombs with multiple upgrades! Also nicely done on the procedurally generated levels, it can definitely help for future versions of the projects or other ones too!
I'm pretty sure most of the comments below covered my main thoughts of improvement, like movement speed or the enemy not being a hazard. One thing I was wondering if there is an objective or end goal for the game since I was going around unsure of what exactly I was trying to do. Even if it doesn't have an end condition, maybe making it something like "Making the strongest bomb to destroy terrain and find treasure!" or "Try to go through as many floors"! Would have been a nice little motive to continue playing the demo.
But for a game concept, I think it is a nice start!