Mr. Shin'iri, an enemy found in Jet Man's stage. He's a tourist carrying a suitcase that runs quickly as if he's late for a flight. When he approaches Megaman, his suitcase explodes into a swarm of Pipis for no apparent reason and he runs even faster in panic. It's as silly as it sounds.
Comet Woman's Mettaurs. They act normally, until they whip out their BFG and fire their Ray Gun until you explode. Frickin' Laser Beams.
In Glue Man's stage, they're actually several Mets stacked atop one another.
During the credits:
Rainbow Man is hanging out with Roll, possibly on a date, which can be a reference to the Megas' song "Don't Mess with Magnet Man".
Hammer Man makes peace with Nail Man by shaking hands. Well, for a given value of "shaking hand"; judging by Nail Man's face, Hammer Man is clearly squeezing his hand tight.
