Mushroom Kingdom Showdown has a total of 25 playable characters in the base game - 18 starter characters, and 7 unlockable characters. Through mods, more characters can be added into the game, such as Mr. L. There is also a boss character that appears at the end of Classic Mode, which is the only boss in MKS.
Ordered in latest Tier List.
|Starter Characters||Bowser • Bowser Jr. • Donkey Kong (DK) • E. Gadd • Fawful • Kamek • King Boo • Koopa • Luigi • Mario • Midbus • Peach • Toad • Waluigi • Wario • Wart • WwwWario (Fan-Character) • Yoshi|
|Unlockable Characters||Diddy Kong • Dr. Mario • Geno • King Bob-omb • Petey • Shadow Mario • Shy Guy|
|Modification Characters||Mr. L • Ashley • Secret Character 1 (MKS2)|
|Scrapped||Master Hand • 8-Bit Mario • Goomba • Nabbit • Sakurai|
- Bowser - The King of the Koopas, who has fought with Mario for over 30 years!
- Bowser Jr. - The son of King Bowser, who fights foes in his Koopa Clown Car!
- Donkey Kong - The big ape from Donkey Kong Island who loves bananas!
- E.Gadd - An old and clever scientist who has created many crazy gadgets!
- Fawful - Fawful is an awful guy who has fury and chortles!
- Kamek - Bowser's wise Magikoopa helper!
- King Boo - The frightening king of the Boos!
- Koopa - One of Bowser's most loyal troops!
- Luigi - The Player 2 that has been in Mario's shadow for too long!
- Mario - The hero that will always save the Mushroom Kingdom!
- Midbus - The brawny, unintelligent minion of Fawful!
- Peach - The damsel in distress, who can fight back with her skill and equipment!
- Toad - Princess Peach's attendant and a long time protector of the Mushroom Kingdom!
- Waluigi - Wario's lanky partner in crime and rival to Luigi!
- Wario - Mario's obese, greedy rival who only loves garlic, and money!
- Wart - An old villain from the world of Subcon!
- WwwWario - The Creator of Mushroom Kingdom Showdown has edited himself into the showdown!
- Yoshi - A cute dinosaur species that helped the Mario Bros. when they were infants.
- Diddy Kong - Donkey Kong's long time partner and friend; armed with a Peanut Pop Gun!
- Dr. Mario - Mario's doctor alter ego; fully loaded with Megavitamins!
- Geno - A warrior sent from the Star Road to fight!
- King Bob-Omb - The king of all Bob-ombs and owner of a power star.
- Petey - The large mutant Piranha Plant that once resided on Delfino Island!
- Shadow Mario - Bowser Jr's alter ego created with a magical paintbrush!
- Shy Guy - The loyal masked warrior of Subcon.
- Giga Bowser - A Transformation of Bowser that makes him more menacing!
- Master Hand (Removed) - The evil right hand that pulls all of the strings!
While every character has alternate costumes, these costumes are different characters (but they still share the same movesets) -
- Dark Bowser (Bowser) - The dark version of Bowser created by the Dark Star!
- Dry Bones (Koopa) - A dried up Koopa who has lost his skin.