Unplayable. Just a blue screen with mute and music buttons. Tested on latest Firefox, Chrome, Opera. And all with latest Flash Player.
Update: managed to make it work using old opera 11.11 .
Game is better than I thought. Nice parody. I even slightly laughed. But still, kinda mediocre.
Plus half a star for Dark Pit bashing. Cuz I'd rather play as Shadow than this edgy Justin Beiber.