I have no clue, I think he is Foofa, it is hard to get their names strait.
Here is all the stars that been on the show:
In its first two seasons, the show featured a wide variety of guests, including Jack Black, Leslie Hall, The Shins, The Aggrolites, Andy Samberg, Cornelius, Biz Markie, Shiny Toy Guns, Supernova, Mark Mothersbaugh, Rahzel, The Postmarks, Sugarland, Tony Hawk, The Roots, Low, Laila Ali, Elijah Wood, Mýa, The Salteens, Sean Kingston and series co-creator Jacobs' band, The Aquabats. In the second season guests included such bands as Enon, The Clientele, Joy Zipper, Of Montreal, Mates of State, MGMT, and The Ting Tings.
Among the varied animation sequences during the show is Super Martian Robot Girl, designed by indie cartoonists Evan Dorkin and Sarah Dyer.[5]
Taking Back Sunday recently filmed an episode for the upcoming season, as did "Weird Al" Yankovic, The Killers, The Roots, Weezer, and Devo.[6]
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