Palette Swap (Super Smash Bros. Melee)

Mario

 * Mario's yellow costume is based on Wario, the same as his previous yellow costume.
 * Mario's blue costume is a red/blue reversal of his traditional colors. This is seen as a partial reference to Mario's varying appearances in games prior to Nintendo's officially establishment of Mario's outfit of consisting of a red shirt, blue overalls and red hat. In various earlier games, Mario occasionally also appeared with sometimes a blue hat, red shirt with blue overalls or a red hat, blue shirt with red overalls. Interestingly however, Mario never appeared in any game with the particular combination of a blue hat, blue shirt, with red overalls as it appears here.
 * Mario's brown and white costume is a reference to Foreman Spike from Wrecking Crew.
 * Mario's green costume is a color inverse of his traditional colors. Contrary to popular belief it is not a reference to Luigi, however it does coincidentally resemble Luigi's colors from the arcade version of Mario Bros.

Luigi

 * Luigi's white costume came from his appearance in Mario Bros.' and Super Mario Bros.''
 * His red costume possibly came from Wrecking Crew.

Peach

 * Peach's yellow costume changes nearly her entire appearance to that of Daisy, including her hair color, hair style, earrings, dress style, gloves, crown and even skin color.
 * Peach's white costume imitates her Nurse Toadstool costume from Dr. Mario.

Bowser

 * Bowser's blue costume came from the international artwork for Super Mario Bros.

Yoshi

 * All of Yoshi's costumes appear as different variations of the Yoshi species in many of his games.

Donkey Kong

 * Two of his costumes came from Donkey Kong 64 ' s "Monkey Smash".

Captain Falcon

 * Captain Falcon's red costume is based off his rival Blood Falcon's outfit, even altering the logo on his back.
 * Captain Falcon's white costume is based off the colors of Jody Summers's outfit.
 * His black costume possibly came from the Japanese commercial for F-Zero X.
 * Captain Falcon's green costume is based off the colors of Pico's outfit.

Ness

 * It is possible his blue costume came from the Devil Machine's eye for the color of Ness's hat.

Ice Climbers

 * The Ice Climbers' orange and red costumes will place Nana in the lead, making Popo follow. The voice samples are swapped to match up with the change.

Kirby

 * Kirby's yellow costume is Keeby. It is also the same as when he is Beam Kirby, sans the hat.
 * Kirby's red costume is the same as when he is Fire Kirby, sans the hat.
 * Kirby's blue costume is the same as when he is Ice Kirby, sans the hat.
 * Kirby's white costume is a reference to his monochrome appearance from the original Kirby's Dream Land for Game Boy. Coincidentally, it is also similar to the colors of Kirby's depiction on the North American box cover of Kirby's Dream Land.

Samus

 * Samus's default costume is her Varia Suit.
 * Samus's pink costume is based off the appearance of the Varia Suit when missiles are selected in the original NES Metroid game. It is also the color of the Gravity Suit in iterations prior to Metroid Prime.

Link

 * Link's red costume is based on the the Goron Tunic from The Legend of Zelda: Ocarina of Time.
 * Link's blue costume is based on the the Zora Tunic from The Legend of Zelda: Ocarina of Time.
 * Link's violet costume resembles the use of the Blue Ring in The Legend of Zelda, this color would later be used in The Four Swords series.
 * Link's black costume is a homage to Dark Link. However, unlike the Brawl version, it is only his tunic.

Mewtwo

 * Mewtwo's green costume is its "shiny" variation in from the Pokémon series.

Mr. Game & Watch
Some of his alternate costumes came from the colored LCD screens.

Marth

 * Marth's white costume is based on Leaf, the protagonist of Fire Emblem: Thracia 776.

Pikachu

 * Pikachu's red costume has it wearing the hat of Red, the protagonist of the original Pokémon installment. It's also based on a "shiny" Pikachu.
 * Pikachu's blue costume has it wearing a blue party hat (like the one in the original).
 * Pikachu's green costume has it wearing a green cowboy hat.

Pichu

 * Pichu's green costume gives it a backback similar to the one worn by Ash in the Pokémon anime.
 * Pichu's blue costume gives it goggles similar to the "Swimmer" class of the Pokémon series.

Roy

 * Roy's red, blue and green costume came from the colored units from Fire Emblem ga

Ganondorf

 * Ganondorf's purple costume possibly represents one of his beast forms' attire.

Dr. Mario

 * Dr. Mario's green clothes are possibly a reference to Rudy the Clown, Dr. Mario's main rival in the series.

Jigglypuff

 * Jigglypuff's yellow palette swap is that of a crown, which has the exact same design as Peach's.

Fox

 * Fox's green outfit is possibly modeled after his father, James McCloud.

Falco

 * Falco's red outfit is assumed to be what he wore when he was not a member of the Star Fox team.

Young Link

 * All of Young Link's colors are exactly the same as Link's, except ordered differently.