The time has come. The great harvest of life. In the end, there is only Xenzarkness. Unfortunately, he never knew how arrogant he really was.
Xenzarkness, lord of the Reapcore telepathically ordered his vast fleet of giant grey mechanical cuttlefish like starships, which transported his massive army of cybernetic slaves to enter a universe, that was ripe for harvesting.
Late at night Scruffy, the janitor with Washbucket at his side was busy silently mopping the floor in the hanger of Planet Express.
Until he heard monstrous roars from outside, followed by the blasting of lasers and screams of terror.
With no time to lose Scruffy became Super Scruffy and thus flew out the window smashing it, followed by blasting out to space, smashing through Xenzarkness fleet, entering one of the Reapcore wormholes. And them speeding towards Xenzarkness to smack him with his mop, causing him to explode and followed by all his Reapcore and cybernetic slaves shutting down. And then Scruffy went back to Planet Express to finish cleaning the floor.
And that's the story of one of versions of Xenzarkness in the multiverse making the mistake of attacking the wrong universe.