Bugs Bunny is a well-known cartoon character from Warner Bros., mostly through his appearances in the Looney Tunes series. He appeared alongside Daffy Duck and Michelangelo in Cartoon All-Stars to the Rescue.
In the Tales of the Teenage Mutant Ninja Turtles episode "Osoroshi no Tabi", when Usagi takes a bite out of a carrot before setting it as an offering to the Tanuki, Raphael chuckles to himself and requotes Bugs' famous catchphrase, "What's up, Doc?"