How many movies have Maxwell Atoms and Richard Steven Horvitz collaborated on?

They have worked on 2 movies together! Their first movie together was Billy & Mandy's Big Boogey Adventure (2007) while their highest rated movie together was Underfist: Halloween Bash (2008). They have not worked together since Underfist: Halloween Bash (2008).

Role
Jeff the Spider (voice)
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Billy / Harold / Pumpkin / Trick-or-Treater Eater (voice)
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Executive Producer
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I'll Cut You Guy / Pirate #2 / Horrorbot / Burnt Skeleton Guard (voice)
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Billy / Billybot / Harold / Pale Ghoulish Juror / Chippy the Squirrel (voice) (as Richard Horvitz)
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Executive Producer
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Storyboard Artist
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