Spoink is a gray, pig-like Pokémon. It has dark, circular eyes, a large gray nose, and small ears. It has stubby arms and possesses no hind legs. Motion is achieved by bouncing on its spring-like tail. The bouncing has a vital function, in that it keeps its heart beating. Even while it is sleeping, it continues to bounce. It wears a pearl produced by Clamperl on top of its head, which amplifies its psychic powers. Spoink will be weakened without a pearl, and always searches for bigger pearls. In the anime it was shown to easily mistake other round objects as its pearl. It lives in mountainous areas. It likes to eat mushrooms that grow underground.
Spoink debuted in Pearls are a Spoink's Best Friend. Ash and his friends first encountered it without its pearl while having breakfast. After scanning his Pokédex, Ash learned that Spoink become tired without their pearls, so he and his friends agreed to help find its pearl. The group soon recovered the pearl, but Spoink lost it again after a confrontation with Team Rocket.
Spoink reappeared in Clamperl of Wisdom. Ash and his friends were sailing to Maisie Island when they spotted Spoink out at sea. A rogue wave knocked Spoink into the ocean, but the group was able to use a life preserver ring to save it. While it was bouncing around on deck, Spoink tripped and lost its pearl out at sea. Despite the efforts of Torkoal and the group's Water-type Pokémon, they were unable to recover the pearl.
The group later met Isaiah, a researcher who specializes in Clamperl. Team Rocket attempted to steal Isaiah's rare blue pearl, but Spoink ended up with the item. Spoink went on to befriend a wild Clamperl and exchanged the blue pearl for Clamperl's pink pearl. Ash, his friends, and Spoink went on to defeat Team Rocket after they stole Clamperl and the blue pearl. Spoink then started to meditate and was able to recover Isaiah's blue pearl in exchange for its pink pearl. However, the kind act left Spoink without a pearl. Realizing the situation, Clamperl gave Spoink the pink pearl as thanks.
Despite Pokédex entries saying that it would die if it stopped bouncing, it has been seen not bouncing many times in the anime.
Despite Pokédex entries saying that its pearl comes from a Clamperl, a Shiny Spoink's pearl is gray, but a Shiny Clamperl's pearl is gold.
In Pokémon Scarlet and Violet, Spoink is programmed to learn Simple Beam through breeding, but no Pokémon in those games can learn Simple Beam, making the move unobtainable until Pokémon HOME was updated. It shares this trait with Psyduck.