When Mario and his friends walk in the arena, Bowser takes out a powerful new weapon that he straps around his waist. He then transforms into a large top made of grey blocks and the game starts.
In the first form, he spins like a top and when it stops, that's your chance to attack. 5 punches or kicks, and the first form is defeated. Next is the large block form which is moving like a Tox Box. Again, 5 good punches and kicks defeats it and the final form kicks in. The final form is the snake which slithers around for a second or two and then it shoots fire. 5 more punches or kicks and Bowser is defeated! The weakness: the Golden Bowser Block!