That's really impressive, have you played a lot of bullet-hell games before? There's some extra content if you beat it with the final weapon, but you'll probably beat it first try as well.
I got back on the game to try extra content which caught me by surprise. I'm gonna try to beat that tonight, and yes this isnt my first bullet hell I'm really into Enter the Gungeon and The Binding of Isaac. I also love the soundtrack it really goes with the game.
