That would be a reference to "The Grim Adventures of Billy & Mandy," the '00s Cartoon Network show about two kids, Billy and Mandy, who befriend the Grim Reaper after beating him in a game.

Cartoon Network shows have created iconic ... the trio are much better as a team than individually. Grim is forced to be Billy and Mandy's best friend after losing a game of limbo.

Super Snowmobile Rally is a crossover Cartoon Network game, with The Grim Adventures of Billy & Mandy characters featured on it. Advertisement Super Snowmobile Rally is a crossover Cartoon Network ...