Morpeko may be a combination of モルモット morumotto ( guinea pig) and 腹ペコ hara peko (hungry, starving). Morpeko eats seeds constantly to keep its hunger at bay. If it's hungry for too long, it grows wild and brutish.

Hunger has disrupted this Pokémon's hormonal balance. The Electric-type energy stored in its cheek sacs has turned into Dark-type energy. Italic indicates a move that gets STAB only when used by an evolution or an alternate form of Morpeko Intense hunger drives it to extremes of violence, and the electricity in its cheek sacs has converted into a Dark-type energy.Even after using up all its dark energy, this violent ruffian will keep running riot until its hunger is appeased. Morpeko ( Japanese: モルペコ Morpeko) is a dual-type Electric/ Dark Pokémon introduced in Generation VIII. If Miracle Eye is used by an opponent or this Pokémon is given a Ring Target, the effectiveness of Psychic-type moves is 1×. When Morpeko enters a battle for the first time, it is in Full Belly Mode and Aura Wheel is Electric-type.

Morpeko has two forms that it switches between with its Hunger Switch Ability: Full Belly Mode and Hangry Mode. It starts battles in Full Belly Mode and switches between forms at the end of every turn while it is sent out. It is always in Full Belly Mode outside of battle. Moves marked with a double dagger (‡) can only be bred from a Pokémon who learned the move in an earlier generation. Hunger hormones affect its temperament. Until its hunger is appeased, it gets up to all manner of evil deeds.While it is not known to evolve into or from any other Pokémon, Morpeko can change forms with its Hunger Switch Ability. Its form also changes the type of its signature move, Aura Wheel.