Yamper is an Electric-type Pokémon introduced in Generation VIII. It evolves into Boltund starting at level 25.
Yamper tends to be drawn to fast-moving things and will chase after people, other Pokémon, or even vehicles. Yamper has an organ that generates electricity from the base of its tail when it runs. It cannot store the electricity it generates, so sparks of electricity can often be seen when it is running. In the Galar region, it is a popular choice for herding Pokémon such as Wooloo. Due to its gluttonous nature, it will only assist people in exchange for treats. Joltik are often seen on its hindquarters, feeding on its static electricity.