"They call me the Traveler, a being of pure energy who watches over the multiverse, viewing the lives that go on, but to never interfere unless absolutely necessary. This is one of those moments. A great evil has unleashed its powers on the multiverse and if it's not stopped, every known reality will be destroyed, that's why I need all of your help, as a team."
Stanford Pines looks around at everyone. "You call this a team?"
"More or less." The Traveler responds.
"Okay then." Ford says turning to the new team. "Let's do a head count."
Tom (Star vs The Forces of Evil):
"A demon with some serious anger issues."
Marceline (Adventure Time):
"A vampire with a decent taste in music."
Lapis Lazuli and Peridot (Steven Universe):
"Two sentient space rocks."
Skips (Regular Show):
"An immortal yeti that works at a park."
Stanford Pines (Gravity Falls):
"And I am the author of three of the most dangerous journals known to man."
"This sounds like a more toxic combination than Malachite." Peridot jokes to which Lapis growls at her. "What, it was joke?"
"I know this may be very strange, but I chose you six because in your own respective universes, all of you are legends." The Traveler responds. "And the multiverse needs your help."
Marceline steps forward. "Well I didn't have anything planned this week. This should be fun!"
The remaining five discuss among themselves and come to an agreement. "Alright we'll help." Skips states. "So when do we start?"
"Now." The Traveler answers creating a ship behind him. "Let's begin."