Johnny Test (2005)

S02E10 Phat Johnny

After a mishap in Eugene's lab, Johnny finds himself gaining weight, mirroring Eugene's own figure. Seizing the opportunity, Johnny decides to channel his new physique into a rap career and to finally snag that video game he’s been eyeing. However, his luck takes a turn as karma catches up with him, leading to a series of unfortunate events that spoil his newfound success.