Like in every SSB game, SSBO has a very large amount of characters hailing from Nintendo or Third-Party universes. The Starting Roster has 57 characters, while 30 characters must be unlocked in certain ways. When the "Challenger Approaching!" screen is shown, the character can be fought on the stage. Defeating him/her will unlock the character. When all characters are unlocked, the All-Star Mode is unlocked. In the game, there are 10 DLC characters that can be purchased from the Nintendo eShop and they do not appear in Story Mode, but appear in All-Star Mode.
Newcomer Characters
Captain Toad
King K. Rool
Kamek
Impa
Tetra
Bandana Waddle Dee
Krystal
Takamaru
Meowth
Sceptile
Isaac
Chibi-Robo
Chorus Kids
Elma
Inkling
Wonder-Red
Rayman
Mii Mage
Mii Athlete
Veteran Fighters
Mario
Peach
Bowser
Rosalina & Luma
Donkey Kong
Diddy Kong
Yoshi
Link
Zelda
Sheik
Toon Link
Samus
Zero Suit Samus
Ice Climbers
Little Mac
Pit
Palutena
Kirby
Meta Knight
King Dedede
Fox
Pikachu
Charizard
Lucario
Greninja
Marth
Ike
Robin
Corrin
Ness
Captain Falcon
Villager
Olimar
Wii Fit Trainer
Shulk
Pac-Man
Mega Man
Ryu
Sonic
Mii Fighters (Gunner, Brawler, Swordfighter)
Hidden Fighters
Luigi
Bowser Jr.
Paper Mario
Dr. Mario
Wario
Mr. Game&Watch
Dixie Kong
Medusa
Dark Pit
Lana
Ganondorf
Skull Kid
Ridley
Ninten
Lucas
Duck Hunt
Falco
Wolf
Roy
Lucina
R.O.B.
Jigglypuff
Mewtwo
Pichu
Zoroark
Mach Rider
Bayonetta
Cloud Strife
Shovel Knight
Banjo-Kazooie
Unlocking Criteria
- Luigi (Play 10 VS matches/Complete Classic Mode/Let him join in Story Mode)
- Falco (Play 20 VS matches/Complete Classic Mode for a second time/Let him join in Story Mode)
- Wario (Play 30 VS matches/Complete 100-Man Smash with Mario/Let him join in Story Mode)
- Lucas (Play 40 VS matches/Complete Target Test with Ness/Let him join in Story Mode)
- Dixie Kong (Play 50 VS matches/Complete Classic Mode with Donkey Kong on Intensity 5.0 or higher/Let her join in Story Mode)
- Jigglypuff (Play 60 VS matches/Complete Classic Mode without any continues/Let her join in Story Mode)
- Dr. Mario (Play 70 VS matches/Reach a total score of 10.000 in Target Test with Mario/Let him join in Story Mode)
- Pichu (Play 80 VS matches/Use Pikachu in 10 VS matches/Let him join in Story Mode)
- Skull Kid (Play 90 VS matches/Clear Classic Mode with Link or Zelda/Sheik on Intensity 5.0 or higher/Let him join in Story Mode)
- Ninten (Play 100 VS matches/Clear 100-Man Smash with Lucas/Let him join in Story Mode)
- R.O.B. (Play 110 VS matches/Collect 200 different trophies/Let him join in Story Mode)
- Bowser Jr. (Play 120 VS matches/Clear Classic Mode with Bowser on Intensity 5.0 or higher/Let him join in Story Mode)
- Ridley (Play 130 VS matches/Clear Target Test with Samus or Zero Suit Samus/Let him join in Story Mode)
- Lana (Play 140 VS matches/Play 15 VS matches on Hyrule Field/Let her join in Story Mode)
- Dark Pit (Play 150 VS matches/Clear Classic Mode with Dr. Mario/Let him join in Story Mode)
- Roy (Play 160 VS matches/Clear Classic Mode with Marth/Let him join in Story Mode)
- Cloud Strife (Play 170 VS matches/Clear Classic Mode with Ryu/let him join in Story Mode)
- Zoroark (Play 180 VS matches/Clear Classic Mode with Greninja on Intensity 5.0 or higher/Let him join in Story Mode)
- Ganondorf (Play 190 VS matches/Clear Target Test with Skull Kid/Let him join in Story Mode)
- Duck Hunt (Play 200 VS matches/Clear Classic Mode with a Mii Fighter class/Let him join in Story Mode)
- Mr. Game&Watch (Play 210 VS matches/Play Cruel Smash with R.O.B./Let him join in Story Mode)
- Lucina (Play 220 VS matches/Clear Classic Mode with Robin or Corrin on Intensity 5.0 or higher/Let her join in Story Mode)
- Medusa (Play 230 VS matches/Clear 3-Minute Smash with Palutena/Let her join in Story Mode)
- Bayonetta (Play 240 VS matches/Clear Classic Mode on Intensity 8.0 or higher/Let her join in Story Mode)
- Shovel Knight (Play 250 VS matches/Reach a total of 100.000m with 10 characters in Home-Run Contest/Let him join in Story Mode)
- Mewtwo (Play 260 VS matches/Clear Classic Mode with Zoroark on Intensity 6.0 or higher/Let him in Story Mode)
- Wolf O'Donnell (Play 270 VS matches/Clear Classic Mode with Fox or Falco on Intensity 6.0 or higher/Let him in Story Mode)
- Paper Mario (Play 280 VS matches/Clear 20 Events after completing the Story Mode)
- Mach Rider (Play 290 VS matches/Clear Classic mode after clearing the Story Mode)
- Banjo-Kazooie (Play 300 VS matches/Clear Boss Rush with 10 characters)
DLC Fighters
Daisy
Young Link
Linkle
Squirtle
Ivysaur
Squid Sisters
Shantae
Solid Snake