The Grumple

"Grumple-ty, Grumple-ty Groo!"

- The Grumple's unlock message

The Grumple is a character that was released on Christmas Eve 2013.

"Enjoy a heart-warming, rhyming children's story about the murderous Grumple! Find the Grumple in the build menu!"

- In Game Message

Simpsons Wiki Description
The Grumple played a character that threatened to steal all of the Holiday cheer of the Winter Holidays in the Krusty’s Kristmas on Ice show. When a fight broke out between the basket ball team and the show skaters (because the preparations for the upcoming game were ruining the show) Homer took matters to his own hands and fought the Grumple, demanding that he return the Holiday cheer.
 * Read the full article here at Simpsons Wiki