Pichu (ピチュー, Pichu) is a fictional creature from the Pokémon media franchise. It is the pre-evolved form of Pikachu and among the first baby Pokémon introduced in the Pokémon series. It appears as a playable character in Super Smash Bros. Melee, and as a trophy in Super Smash Bros. Brawl and Super Smash Bros. for Nintendo 3DS.
Pichu is described as small, bipedal mouse with an oval-shaped head, a black, spiky pattern around its neck, and large, arrowhead-shaped ears tipped with black markings. As the pre-evolved form of Pikachu and a baby Pokémon, Pichu is less powerful than its evolved forms. While it cannot learn some moves that Pikachu and Raichu can, it can learn three moves (Charm, Sweet Kiss and Nasty Plot) that its evolved forms cannot. Pichu only evolves into Pikachu when it reaches a very high level of friendship with its Trainer.
The Pokédex explains that the electricity pouches in Pichu's cheeks are still small and unable to store much electricity yet. This, in turn, makes it inexperienced with handling electrical attacks, to the point that it occasionally inflicts damage to itself. While this does not actually occur in the Pokémon games, it has been demonstrated in both the Pokémon anime and Super Smash Bros. Melee. Additionally, its evolutionary family's signature move, Volt Tackle, will deal recoil damage after being successfully used.
Due to its inexperience with handling electricity, Pichu may discharge it accidentally and spontaneously if amused or startled, and vice versa. Despite its small size, it can zap even adult humans, but it surprises itself whenever it does so. When it plays with other Pichu, they may short out electricity with each other, creating a shower of sparks, startling them and causing them to start crying. It gets better at holding power as it grows older, where it starts playing with other Pichu by touching tails and setting off sparks in apparent mutual tests of courage. It charges itself with electricity more easily on days that either have very dry air or has thunderclouds, in which case the crackling of static electricity can be heard coming off of it.
In Super Smash Bros. Melee
As a playable character
Main article: Pichu (SSBM)
Pichu is a playable unlockable character in this game, albeit as a perceived "joke character", due to being an intentionally inferior clone of Pikachu that possesses many significant weaknesses. Melee is notably the only game that is true to Pichu's Pokédex description of harming itself with its own electricity: whenever Pichu performs an electrical attack, it will sustain 1%-4% recoil damage. Along with this, it is also the lightest character in Melee, giving it extremely poor survivability overall. It is ranked 24th on the Melee tier list, placing it in the G tier and being the third lowest spot on the entire tier list.
A Tiny Mouse Pokémon identifiable by its big ears, Pichu evolves into Pikachu. It's not very skilled at storing up electrical energy and will sometimes discharge it if jarred. Although it's small, it has enough electrical power to give even an adult quite a shock. It's often startled by its own power.
In Super Smash Bros. Brawl
Pichu is one of the five playable characters in Melee who did not return as a playable character in Brawl, and is the only one who neither has unfinished data on Brawl's disc nor a new playable character as a clear replacement. Instead, Pichu only appears as a trophy. However, a couple of its unique attributes in Melee (its ability to wall jump and the blue goggles from its blue alternate costume) were given to Pikachu.
As a Trophy
Pichu makes an appearance in Brawl as a collectible trophy. It is obtained by completing All-Star Mode without using a continue. The trophy describes Pichu's appearance in the Pokémon games, and makes no reference whatsoever to its appearance in Melee:
A Tiny Mouse Pokémon. Because its electric cheek pouches are still small, it cannot store electricity yet. Pichu has been known to flaunt its courage by touching tails with others and setting off sparks. It is easier for Pichu to build up electricity when the humidity is lower. Pichu will evolve into Pikachu.
Pichu once again did not return as a playable character in Super Smash Bros. 4. However, Pichu does return as a trophy in Super Smash Bros. for Nintendo 3DS. In Super Smash Bros. for Wii U, it is referenced in the Palutena's Guidance on Pikachu, as Viridi discusses its evolutionary family.