I really like the visual style, it looks clean and polished. The gameplay itself feels heavy, the character has a very long acceleration time, I really wouldnt mind this if this could be somehow explained (if the character was really fat and with large mass). There is no way to tell how much health the player has. After getting to the helmet part, I was a bit confused about the controls, only to later find out that I was playing as the enemy that I thought I was supposed to fight. This kind of abrupt perspective shift really needs to be handled more gracefully. There was also no way to tell if I was making progress or not fighting the player, so it felt like I was doing nothing. Some visual or audio feedback to progression would really help. As for the theme, I think it adhered relatively well since it included a dungeon of some kind.
But more importantly, give the player feedback for anything that should be meaningful in any way.