Pikachu is a playable character in the fighting video game, M.U.G.E.N Trilogy. It was confirmed along with the other characters from the original Super Smash Bros. video game on January 24, 2015. Ikue Ōtani reprises her role as Pikachu while using recycled voice clips from various Super Smash Bros. games.
Pikachu is a small, rodent-like Pokémon, and is categorized within the Pokédex at #025 as the "Mouse Pokémon". The extensive variety of Pokédex entries available for Pikachu throughout the Pokémon series provide plenty of biological information, such as how it lives in forests in groups away from people, and how it keeps its tail raised as it monitors its surroundings.
In the core series, Pikachu is a relatively weak Electric-type Pokémon that can be found early in the series' first generation of games: Pokémon Red, Green and Blue Versions. Unlike certain Pokémon that had plot elements wrapped around them, such as Mewtwo, Pikachu was simply a Pokémon that could be readily caught, evolved into a stronger form (Raichu), and had no bearing on the story.
How to Unlock
Use Pikachu's Super Smash Bros. amiibo or scan its AR icon from the M.U.G.E.N Trilogy website.