Boomer...
"Gasp....having an attack...."
~ Boomer

Whoa, de ja vu! Why does this look familiar?? Boomer has the honour and vigour of a samurai, but the fighting abilities of that guy from gym glass you beaned with a dodge ball last Tuesday.  Boomer can be fierce, but if you take Mario, Geno and Bowser at the aforementioned levels, you might be able to destroy him pretty quick! They should all be wearing their brand-spanking-new armor from Croco, and Mario should have the Lazy shell and the Rare Scarf. Geno takes the Star Gun (If you didn't get the Star Gun, the Hand Cannon will do) and the Quartz Charm, and Bowser has the Drill Claw (if you didn't get that, the Spiked Link) and the Jinx Belt. Boomer will turn red, then blue again, but you might be able to destroy him before this. When Boomer screeches and says something about how this can't be happening and he's having an attack, you'll know you've won. But you won't have much (in fact, you'll not have any) time to take a breather...