Pikachu is one of currently 62 unique fighters participating in the Super Smash Bros. fighting competition featuring many popular video game characters, most of them under contract to Nintendo. This series has spawned 4 video games of its own, with Pikachu appearing in all four of them.
Pikachu is an Electric-type mouse Pokemon that can be caught and trained in many Pokemon games, and is capable of numerous abilities related to electricity. Given that Pikachu is the mascot of the franchise, Pikachu has been part of Super Smash Bros. since its start in 1999.
The Pikachu specimen that has been in SSB,, at least in the context of The Real Smash Bros., is the same one that has belonged to Pokemon trainer Ash Ketchum from Pallet Town since the very first episode of the Pokemon anime. As a result, this Pikachu has gone on as many adventures as some of the other fighters in SSB, like Mario, Link, Samus Aran, and Kirby.
In 2008, most of the characters that would participate in SSB during what came to be known as the "Brawl" era were thrust into an adventure of a lifetime that threatened the very world in which we lived in. Titled "The Subspace Emissary", most of the Smashers had to save the world from a being known as Tabuu. During this time, many Smashers formed lasting bonds with one another. Pikachu, in particular, bonded with Samus Aran after she rescued him in the Research Facility. The two have been close friends since then. For the rest of the Brawl era, Pikachu would often shock Snake whenever he tried to flirt with Samus.
Through Pikachu, Samus became friends with Ash, and eventually, his stable of traveling partners. Samus does not have any romantic feelings for Ash, as even she knows his heart belongs to Cerulean City Gym Leader Misty Waterflower, the very first travel partner Ash ever had.
Pikachu's normal entrance music, appropriately, is "Thunderstruck" by AC/DC. Sometimes he may enter to the same band's "High Voltage", or to "Blow My Fuse" by Kix.
Being a mouse, Pikachu is especially fond of cheese, as is tradition for mice in fiction (heh, that rhymed). Mario will often share his Italian cheeses with Pikachu, knowing that mice are cheese enthusiasts. Pikachu's fondness for cheese is not limited to just plain cheese. He will eat anything that is cheese-based, like pizza, quesadillas, and even snacks like Cheez-Its, Cheese Nips, and Cheese Ritz Bits Sandwiches.
Pikachu also believes that mammals are superior to other classes of living beings, as he confides this to Samus in an early episode of the series.
Since this is the same Pikachu from the anime, Pikachu also likes ketchup. He often eats it with cheese.
Other than those with Samus and Ash, Pikachu's relationships with other residents of the Smash Mansion - and indeed, some outside the mansion, are quite complex.
As is the case with Pikachu, the Jigglypuff specimen in Smash is a very famous specimen from the Pokemon anime - the one that followed Ash and his friends around throughout Kanto, the Orange Islands, and Johto. Whenever she ran into them, she would often sing to them, but everyone would be asleep before her song was over. This pisses her off intensely, and so she retaliates by drawing on their faces. She has exhibited this very same behavior in the Smash Mansion.
When it was confirmed a self-sustaining Charizard would be fighting in Smash starting in 2014, it was revealed that this would be the same Charizard that belongs to Ash. Pikachu and Charizard go way back, as Charizard was one of the first Pokemon Ash ever obtained on his journey, back when he was a Charmander. As an unevolved Pokemon, he was obedient towards his master, but once he became Charmeleon, his personality changed, disobeying Ash's orders, much to Pikachu's consternation as well as Ash's. This did not change with the evolution to Charizard, who soon only fought who and when he pleased. However, when Ash devoted a lot of time to saving Charizard's life after a battle with a Poliwrath on the Oranges left him frozen, Charizard opened up to him. Pikachu and Charizard, likewise, repaired their friendship.
Pikachu met Dawn's Buneary when she first acquired the rabbit Pokemon. The brown rabbit took an instant liking to the yellow mouse; though Pikachu was resistant at first, he eventualy reciprocated feelings back for her. In 2014, it was revealed that Buneary was pregnant with a litter of baby Pokemon and that Pikachu was the father.
Ash's other traveling partnersEdit
Pikachu has made friends with all of Ash's friends over the years, but he knows that the only girl Ash wants is Misty. Pikachu was not thrilled when Misty said she had to stay at her Gym for a while so her sisters could do something else, though Pikachu has warmed up to the other female traveling partners of Ash, but Pikachu has not tried to pair any of them with him.
Other cartoon miceEdit
Every Thursday Pikachu has other cartoon mice come over to hang out with him, from famous names like Mickey Mouse (Disney), Jerry (Tom and Jerry, MGM), Speedy Gonzales (Looney Tunes, Warner Bros.) to lesser-known ones like Maisy, Herman (Herman and Katnip, Famous Studios), and even Mighty Mouse (Terrytoons). Pikachu is generally recognized as the most famous animated mouse in non-Western animation.