"You are immortal" LOL, is that a bug or a feature? ;) Anyway, I loved this. The music was great, and the cactus' design is very cute! I liked the punching animations as well. A couple of rooms in the second level of the dungeon had disembodied bits of laser floating around. And I think I must have reached the end, because I went through a door with the white glow and ended up walking through an area of blackness. So there's that.
Fantastic work!