Piplup is a light-blue, penguin-like Pokémon, which is covered in thick down to insulate against the cold. It has a dark blue head with a primarily white face and a short, yellow beak. The dark blue feathers on its head extend down its back and around its neck, which causes it to appear to be wearing a cape. There are two white ovals on its chest and a small, light-blue marking resembles a crown above its beak. It has flipper-like arms and yellow feet with three toes each.
Piplup has a strong sense of self-pride. Because of its pride, it has a hard time accepting food from humans and bonding with its caretakers. It will even puff out its chest after it falls down, which it often does due to its poor walking abilities. However, it is a skilled swimmer that can dive for over ten minutes in order to hunt. It has also been shown to fly short distances in the anime. It lives along the seashore in colder climates.
In Super Smash Bros. Brawl for the Wii, Piplup was a Pokémon that could be released from a Pokéball. Once released, it would use Surf to knock players off of the stage. It's not as dramatic as other attacks can be, though it can cause players to get KO'ed if they're not careful and don't recover to get back onto the stage. Piplup also appeared as a trophy and a sticker.
Piplup debuted in Following A Maiden's Voyage!, where he got into a fight with a Chimchar over their food in Professor Rowan's lab. After ruining the lab, the two escaped, and Dawn was given the task of finding them. She found Piplup, and the two narrowly escaped an Ariados attack. Back at Rowan's lab, Dawn chose Piplup as her first partner Pokémon. Since then, he has been her main Pokémon and has been mostly seen outside of his Poké Ball.
Prefers cold climes and appears along coasts. It's an adorable little thing—as cute as any child—but it's also prideful, unwilling to accept handouts from people.