What cartoon is about a cat turning into a hippopotamus? - briefly
The cartoon you're referring to is "Tom and Jerry." In one of their classic episodes, Tom tries to turn Jerry into a hippopotamus using a machine, which ultimately backfires on him.
What cartoon is about a cat turning into a hippopotamus? - in detail
The animated series in question is "The Amazing World of Gumball." This show, created by Ben Bocquelet and produced by Cartoon Network Studios, follows the adventures of a blue cat named Gumball Watterson who lives in the town of Elmore. In one of the episodes, titled "The Colossus," Gumball accidentally drinks a growth potion that transforms him into a massive hippopotamus-like creature. This transformation leads to a series of humorous and chaotic events as Gumball struggles to adapt to his new size and learns valuable lessons about self-acceptance and responsibility. The episode is known for its clever writing, vibrant animation style, and the unique blend of comedy and heartwarming moments that characterize the entire series.