The Test (S05E08)

Gumball is livid when an online test keeps telling him that his character-type is "The Loser". He's convinced the only way to shake off this label is to do the opposite of everything he normally would. But Gumball suppressing his natural instincts leaves a vacuum, a Gumball-shaped hole that someone has to fill. That someone is Tobias, who starts turning the whole show into a cliched sitcom. (iTunes)