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When Billy fails an important test, the result of which will go into his permanent record, he asks Grim to magically alter his grade from an "F" to an "A"; as Grim reluctantly changes the grade, Billy becomes a genius, but reality is thrown completely off balance. Mandy and Grim go back in time to stop the past Grim from helping Billy, but it does not work. They keep going back in time to different epochs, each time meeting another Grim, eventually trying to stop Billy's ancestors from conceiving him, but nothing works. After meeting Billy's distant dinosaur relative, the episode ends abruptly as Grim wonders what the end of this could be.
Prima Aeris Date : Aug 24, 2001
Aeris ultimum diem : Nov 09, 2007
Episode : 184 Episode
Season : 7 Season
runtime: 11 minutes
Studio: Cartoon Network
Patriam: United States of America