- Not to be confused with List of unused content of Super Smash Flash 2.
The following lists consist of removed content previously shown in a demo before being scrapped or altered from its original implementation. Note that normal attacks are too numerous to list due to being changed constantly; as such, they will not be mentioned below.
- Mario's F.L.U.D.D. was removed in demo v0.2b.
- Heat Shield and Fire Mario Eruption were Fire Mario's side and down special moves respectively until demo v0.5a.
- Wario's Wario Bike was replaced with Chomp in demo v0.8a.
- Sheik's Chain was replaced with Bouncing Fish in Beta 1.0.
- Airlift replaced Rhythm Twister as Tails' side special move in Beta.
- Remote Robot replaced Tails Whirlwind as Tails' up special move in Beta.
- Rolling Cutter was replaced with Super Arm in demo v0.6 as part of Mega Man's Weapon Change and Weapon Use. Both moves, in turn, were completely removed in Beta. Water Wave took the place of Weapon Change, and the Mega Buster became Mega Man's only neutral special move.
- Proto Shield was replaced with Crash Bomber as Mega Man's side special move in Beta.
- Lloyd had a set of techniques called "Linked Artes" in versions 0.8a and 0.8b. These techniques allowed Lloyd to instantly cancel certain moves into into each other in rapid succession. They were removed in v0.9a, as they were found unnecessary.
- Guardian was Lloyd's down special move, but was replaced with Grave Blade in demo v0.8a. Subsequently, Grave Blade was replaced with Rising Falcon in Beta.
- Beast replaced Sonic Thrust as Lloyd's side special move in demo v0.5a only for Sonic Thrust to be brought back in demo v0.6 and Beast to be relocated to Lloyd's forward smash. Sonic Thrust then became Lloyd's dash attack, as Tempest replaced Sonic Thrust as his side special move.
- Sora's special moves were changed multiple times. In v0.6, his down special move was Magic Swap. It got replaced by Thundaga on v0.8b, which, in turn, was replaced by Command Deck in Beta.
- When Thundaga replaced Magic Swap, Blizzard (part of the move) became his back throw, while Firaga (also part of the move) became his neutral special move. Command Deck, however, made all three spells part of it.
- Strike Raid, in v0.9b, was moved from Sora's side special move to his neutral special move, to accommodate Flowmotion.
- Aerial Recovery replaced Finishing Leap as Sora's up special in Beta.
- Stunning Slash was Ichigo's down special move up until demo v0.2a.
- Bankai Ichigo's down special move was a weaker Kuroi Getsuga until demo v0.2b, where it was replaced with Multislash, which up until that point was his neutral aerial.
- Ōdama Rasengan was the fully-charged version of Naruto's Rasengan, but it got replaced by Fūton: Rasenshuriken in demo v0.8a. Ōdama Rasengan made a resurgence as part of Tailed Beast Rush in Beta 1.2, however.
- Naruto's side special move was originally Fūton: Rasenshuriken before it got replaced by Shuriken, which in turn got replaced again in demo v0.8a, by Shadow Clone Toss. Rasengan Smash was originally Naruto's down special move before Shadow Clone Summon replaced it.
- Krystal Phase was originally Krystal's side special move, but was removed in the development of demo Beta 1.2.
- Fire Mario was Mario's Final Smash up until version 0.9b, where it was replaced by a revamped Mario Finale.
- Peach's Final Smash was Peach Beam until Peach received a resprite in the Beta version, causing the attack to get replaced with Peach Blossom.
- Random Encounter was Black Mage's Final Smash until it got replaced by Warriors of Light in Beta 1.2.
- Bankai Ichigo, Kyūbi Naruto, and Super Saiyan Goku got respectively replaced by Mugetsu, Tailed Beast Rush, and Meteor Combination in Beta 1.2.
- Super Adapter was Mega Man's Final Smash until it got replaced by Mega Legends in Beta 1.2.
- Test Stage 1 and Test Stage 2 were removed in demo v0.5a and both got replaced with the Waiting Room.
- Temple of Time was replaced with Hylian Skies in v0.9a.
- Castle Wily was replaced with Skull Fortress in v0.9a.
- Bandana Dee and PAC-MAN were both removed as Assist Trophies in Beta, due to their new roles as playable characters.
- Amigo was removed as an Assist Trophy in Beta, due to being never fully functional and because his music never picked up where it left off.
- Renji Abarai was replaced with Rukia Kuchiki as an Assist Trophy in Beta, due to being excessively buggy with floor collisions, teleporting around, and slippery movement.
- Light Yagami was removed as an Assist Trophy in Beta, due to being "completely overpowered" and originating from an anime franchise with no other representation in Super Smash Flash 2.
- MissingNo. was removed as a Poké Ball in Beta, due to its function being deemed redundant, along with reports of having scared users playing in fullscreen mode into mistakenly thinking that their computers had actually crashed.
- Main article: Background character/Removed background characters
|Central Highway||Bee Blader|
|Gangplank Galleon||Scurvy Crew|
|Green Hill Zone||Cream the Rabbit|
|Hueco Mundo||Sōsuke Aizen|
|Saturn Valley||Rope Snake|
|Sky Sanctuary Zone||Mecha Sonic|
|This section requires to be rewritten or expanded.
The information is not outdated nor incomplete, although it can be rewritten for a more formal explanation and better clarity. It may require an expansion going further on missing details.
- Mario's original Super Mario World sprites were recolored to match the style of Super Smash Bros. Brawl in v0.5a. He was resprited, and then recolored once again, to match Super Smash Bros. for Nintendo 3DS and Wii U, both changes happening in v0.9b patches.
- Kirby's sprites were changed from rips from the Game Boy Advance and Nintendo DS Kirby games to Brawl-styled sprites from Kirby Super Star Ultra in v0.5a. He was then resprited again in Beta.
- Link was given completely custom sprites for v0.9b. He was later recolored to match his color scheme in Super Smash Bros for Nintendo 3DS and Wii U.
- Naruto had his color scheme altered in a patch for v0.9a. Goku and Ichigo received the same treatment in v0.9b, while Pikachu and Lloyd were changed in Beta. The latter also had a correction of his swords, preventing him from flipping his swords based on the direction he faces.
- Multiple characters, most notably Tails, got minor tweaks to their color scheme in Beta 1.2.
- Temple has received multiple sprite changes from demo to demo.
- Hueco Mundo, Twilight Town, and Rainbow Route were completely reworked and redesigned in demo v0.9a.
- Tower of Salvation, Clock Town, Central Highway, Dream Land, Fourside, and Battlefield were resprited in demo v0.9b.
- Pokémon Stadium 3 has been resprited and renamed to Pokémon Colosseum in Beta.
- In Galaxy Tours, the Comet Observatory got replaced with the Starship Mario as the stage's main form in version Beta.
- Dracula's Castle, Saturn Valley, Sky Sanctuary Zone, Yoshi's Island, Planet Namek, Bomb Factory, Crateria and Final Destination have been overhauled in version Beta.
- Waiting Room got a complete overhaul from v0.8b to v0.9a, but then was altered again from 0.9b to Beta; in v0.9b, its sides were walls extending to the lower blast zone. In Beta, it was given slopes on its underside similar to the original Online Practice Stage.
- Activating the Smash Ball to perform a Final Smash was originally much different. Players would have to pick it up from the ground and activate it by shielding and then pressing the special move button.
- The command to use a Final Smash changed to simply pressing the special move button in v0.2a, but it would not be until v0.2b that the Smash Ball is a floating item rather than one players can pick up.
- Lakitu originally had a much different function as an Assist Trophy, following the player who summoned it and catching it with a fishing rod if it fell off-stage. As of Beta, Lakitu now floats high across the stage and drops Spinies drop down that will attack opponents they make contact with.