The game feels great, legitimately feels like a dungeon that could appear in Zelda or something. I loved seeing what each different animal did, and I loved all the little animations on each one.
At first, I wished that the game was less harsh when you died -- but I played one more time, and I found that it actually added to the Game Boy-ish old-school hard feel of the game. I found myself taking the controls more seriously and playing more carefully.