Lol, that's great. The skill in that is like an Osu! player's dream. Also the broken textures at 6:10 are a great representation of some of the glitchy hell that comes about with Pokémon R/B/Y exploits. The animator did a fantastic job.
I'm becoming quite partial to some bullet hell, but only if the rest of the game is up to scratch. Grindea? Yes. Issac? Yes. My most recent discovery, Rabi Ribi? No. The boss battles are great and usually satisfying to complete, but the game is lacklustre in so many other areas that it's a bit of a disappointment. My review for it was so long that Steam flat out refused to accept it. Sadly I've outstayed my 2 hours for a refund, so I guess I'll probably get round to completing it some time.