User blog comment:Bowser & Jr./New NSMBU Images/@comment-26124383-20120908224150/@comment-5522550-20120909085135

Okay, so umm...

Mario, Luigi, Yellow Toad, Blue Toad, and Miis are the only playable characters, the plot for this game is that Princess Peach is kidnapped by Bowser, and the bosses are the Koopalings with Boom-Boom as the fortress boss. :3