In the Japanese version, two games featured in the Nintendo Chronicle list are Jump Super Stars and Jump Ultimate Stars, a duology of Smash Bros.-styled fighting games released for the Nintendo DS that serve as crossovers between several Shonen Jump properties. Coincidentally, both games feature Goku from the Dragon Ball series, a highly-requested non-gaming character for the Smash Bros. series.

A voice line of Snake saying "There!" can be found in the game's files.

While it remains unused in this game, it would later be used for when Snake plants a C4 in Super Smash Bros. Ultimate.

Inside the game’s files are unused animations of Diddy Kong laughing. The file names suggest that it would’ve been used when using the Banana Peel down special.

Like its predecessor, Super Smash Bros. Melee, The game was originally supposed to include alternate trophies along side their regular trophies for the playable characters. No icons nor preview images exist for any of the trophies.

There is an unused model of Luigi with blue clothing which differs quite a bit from both Luigi's and every other character's model. One interesting difference is that this costume has its shadow model integrated into the model itself, rather than having it as a separate model.

In this version of the Yoshi's Island stage, if a player's shield breaks while they are standing on one of the sloped parts at the end of the main platform, when they land they will roll off the stage, canceling the shield break stun. This allows the to immediately regain consciousness and move much sooner than intended.

Wolf, Jigglypuff, and Toon Link were not involved with the plot of the Subspace Emissary due to them being close to not appearing in the final roster.

Wolf barely made it into Super Smash Bros. Brawl due to time constraints. He was added to the game because of popular demand, and because he was an easy character to create.

The stadium in Home-Run Contest is actually a loop. After 40,000 ft, it will go back to zero.

In the Subspace Emissionary there were plans to include a scene where Meta Knight still had control of the Halberd, before being attacked and losing the ship to Tabuu. This scene was removed from the final game.

Super Smash Bros Brawl was Samus's first appearence that featured voice acting, as Zero Suit Samus has several spoken taunts. Before this, only three games had had her say any lines: Super Metroid, Metroid Fusion, and Metroid: Zero Mission; these lines were only in text format and were unspoken.

The Mario Circuit stage has its entire stage modeled out. It even has some blocks and trees in the distance.

Smash Bros. Director, Masahiro Sakurai, has stated that Shigeru Miyamoto had approached him about adding Pac-Man into Smash Bros Brawl. Sakurai imagined Miyamoto inferring to adding Pac-Man in his original 2D form to the game, and that the idea would be "too farfetched".

The Japanese release includes a 5-minute demo of Mother 2 (known as EarthBound in West) and a 3-minute demo of "Fire Emblem: Monsho no Nazo" within the Masterpieces menu.

There's is an unused enemy called Mizzo which is never found in the Subspace emissary except during the enemy display room inside the Halberd. It appears to be an orb with arms and legs sticking out, surrounded by wind. However, a trophy exists for this enemy which will spawn randomly wherever trophies can spawn. The trophy description references this enemy's absence.

Using a camera hack in the Pokemon Stadium stage, it's possible to see a hidden building with the word "Pocket" written on it. This is the first word in "Pocket Monsters", the Japanese name for Pokemon.

This appears to be the Saffron City stage from Smash Bros 64.

Masahiro Sakurai stated that the Villager from Animal Crossing was removed from Brawl during the planning stages because "he wasn't suited for battle".

The track "Castle / Boss Fortress (Super Mario World / SMB 3)" was originally going to be in the Delfino Plaza stage, but was later moved to the Luigi's Mansion stage instead.

There is unused tile for the Stage Builder which can't be used normally. It resembles a bump, and is fully functional.

An unused graphic of the Mario icon from Super Smash Bros. Melee can be found in the game's files. The Mario icon could mean that all the icons were going to be reused from Melee, but it also could have simply been a placeholder graphic.

Whilst the Star Fox Characters were voiced by their English Voice Actors from Star Fox: Assault in Super Smash Bros. Brawl, half the cast were actually unavailable to return. Some characters were instead given new voice actors:

•Falco and Peppy were voiced by Dex Manley, who voiced ROB 64 in Star Fox Assault.
•Wolf was voiced by Jay Ward.
•Leon was voiced by Jim Walker, who also voiced Fox.
•Panther was voiced by Eric Newsome, who also voices Meta Knight in the game.

Sakurai considered making Miis Playable, but decided against it. According to Sakurai, it didn't seem right at the time to have Miis punching and kicking. Miis were however added in the game's sequel six years later.

A black Nintendo DS Lite can be found in the boxes on one of the backgrounds in diorama mode.

In Super Smash Bros. Brawl, Sonic's victory theme is actually the "Stage Clear" theme from Sonic the Hedgehog 2006, making it the only victory fanfare taken directly from another game.

There is an extensive amount of music that is listed within the game's data, but the tracks themselves are not present in the final version.

An unused HUD element named "InfAdvLevel0000" was apparently intended to display a shrinking bar for 50 frames (5/6 of a second) with a "level number" in a circle. The label "pp" is even more mysterious. The black areas of the textures would have been transparent in-game.

During the Subspace Emissary, Ike will shout "Great Aether!" before attacking the Ancient Minister in a cutscene. However, the attack he does is merely a normal Aether.

This may have been done to match the pacing of the Japanese version, where he says "ten" as he leaps into the air, and "kuu" as he swings his sword down.

There are multiple glitches that can occur if a character begins their Final Smash as the bridge is reforming in the stage 'Bridge of Eldin". The most notable of these is that R.O.B. will enter his final smash, Diffusion Beam, and stay in that state for the rest of the match, no matter how long. He will also remain invincible.

With enough damage, it is possible to "destroy" a Landmaster, forcing the final smash to end early. However, without hacking, it is extremely difficult to pull off.

An unused subaction and corresponding animation exist for Zero Suit Samus' Plasma Whip Side-B, labelled "SpecialSItemGet". There are also two other unused throwing animations for Samus are labeled "SpecialSThrowS" and "SpecialSThrowHi".

Presumably, the attack would originally have grabbed items from a distance and slung them away as a projectile, a function that would have been unique to the character. It may have been removed due to it interfering when players were attempting to hit another player with the whip.

An unused character select screen exists in the game for a wi-fi mode named Slipspace. This mode is limited to "With Anyone", and unlike regular wi-fi modes, there is no space on the screen for additional players to join. In the settings bar, the player can set the number of minutes for the mode.

How this mode would have worked and whether it is operational in the game is unknown. The description text for the mode is:

Wolf has an unused attack animation which looks similar to that of Fox's rapid kick.

The stage "Green Hill Zone" has a large amount of extra geometry outside of the camera view, a fact that the game's director, Masahiro Sakurai, noted on the Smash Bros. Dojo when the stage was revealed.

An unused character select screen menu exists in the game for a wi-fi version of Boss Battles. It is unknown if this mode is functional and why it goes unused.

The description text for the mode reads:
"Take on 10 bosses with the help of a friend! (2 players)"

Kirby has an unused animation that appears to be him walking with a hammer and then swinging it with full force in the same manner as King Dedede's Jet Hammer move. One Smash-focused Nintendo Direct in April 2014 included footage of Kirby charging up and releasing his hammer, in Super Smash Bros. for Wii U

Fox and Falco both have unused animations that appear to be their blasters misfiring.

The "Shellcreepers" trophy states that Mario and Luigi used to fight these enemies "back when they were plumbers", though there has been no actual mention of them retiring throughout the Mario series.

Solid Snake can be seen hiding inside the Cardboard Box trophy.

There are unused CD labels in the games files, stored with the data for the CDs that are found during battles. It is likely that the CDs were originally intended to show these labels related to what would have been unlocked when collecting them.

The Primid's faces in the Subspace Emissary change every time the game is started.

There is some red text written in an empty area of Snake's head texture near the hair tufts. The text reads "def n_f_o layer" and is hidden by alpha transparency. The text can also be found for each of his alternate colors.

Marth's trophy information is not entirely correct, as it says Altea was destroyed by Akaneia. In actuality, Akaneia only controlled Altea for a period of time, and is reclaimed by Marth near the end of the game.

Many elements of Solid Snake are actually taken from Naked Snake (AKA Big Boss) in Metal Gear Solid 3.

Sometimes when Snake uses his C4, it is in the shape of a butterfly, an homage to Naked Snake shaping C3 into a butterfly before planting it onto a fuel tank in Metal Gear Solid 3: Snake Eater.

If the player does the down taunt command in a split second at Shadow Moses Island, the Codec will appear. One of three characters will appear (Colonel Roy Campbell, Hal Emmerich, or Mei-Ling) and give a short description of any random character on the battlefield.

Snake appears to dislike Sonic according to his Smash Taunt conversation with Otacon when battling the hedgehog. Whilst the reasons are mostly unclear, one popular theory is that it references how Snake's Japanese VA, Akio Otsuka, is the son of Chikao Otsuka, who voices Sonic's nemesis, Doctor Eggman/Robotnik. Coincidentally, Chikao also voices Big Boss in Metal Gear Solid 4. It's also possible Snake's disliking of Sonic is a reference to how hedgehogs eat snakes in the wild.

The reason that Snake was included in the game was to satisfy Hideo Kojima's son, who was a big fan of the series and wanted to see one of his father's characters in the game. Kojima was also hoping to expose younger players to the character as The Twin Snakes was the most recent Metal Gear game on a Nintendo platform. Kojima had also previously desired Snake to be in Super Smash Bros. Melee.

Sonic the Hedgehog can outrun the F-Zero vehicles on the Big Blue Melee stage if he has the Bunny Hood equipped .

Both Ness and Lucas are unable to learn their Final Smashes (PK Starstorm) in their respective games. Instead, it's a move that both Poo (Ness' partner) and Kumatora (Lucas' partner) learn. In both Final Smash trophies, it says the partners taught them the move so that they could use it in Brawl.

In the Port Town Aero Dive stage, there's a giant R.O.B. with glowing red eyes.

There is evidence suggesting that Pikachu in this game is actually Pichu from Super Smash Bros. Melee, albeit evolved:

•Pikachu in Brawl uses Pichu's wall jump ability from Melee.
•Pikachu's Final Smash in Brawl is Volt Tackle, which, in the Pokemon games, can only be inherited by an egg-born Pichu.
•Pikachu's blue costume in Brawl uses the goggles worn by Pichu's blue costume in Melee.

According to an IGN interview, Super Smash Bros. Brawl's motion controls were hard to work into the game, possibly due to their impreciseness. Instead, the game was focused on the Wii's internet capabilities.

Super Smash Bros. Brawl was originally planned as a launch title for the Wii, meant to showcase the difference between the Gamecube and the Wii (mainly via online capabilities), just as Super Smash Bros. Melee showcased FMV and graphical capabilities that the N64 was incapable of.

Yoshi's saddle is missing in the Super Dragon trophy.

By looking through the game's disc you can find different victory fanfares signed for each character, there's even fanfares for both Mewtwo and Roy. But in the final game, Meta Knight is the only character with a unique fanfare.

The US version of the Baby Mario trophy claimed that "he lacks overalls", even though the trophy itself depicts him with his trademark red/blue overalls.

Despite not appearing in the Subspace Emissary, Crazy Hand's trophy is placed in The Supspace Emissary category.

The Sothe trophy states that he is a swordsman - this is untrue, as Sothe wields knives and daggers.

Moltres' trophy says that its first game was Pokemon Gold and Silver, when it really originated in Red and Blue.

On the Kyle Hyde trophy, it states that he is a former detective. This is not true; Kyle is a former cop who worked for the NYPD.

The Bonkers trophy says that Kirby could get the Smash ability by inhaling him. This is not correct, as he only gives the Hammer ability.

Lucas' home village is stated to be call "Tazumili" in the US version, but in Mother 3 the village is actually named Tazmily. This was corrected in the PAL version of Brawl.

During the opening cutscene, hidden characters are not shown until they are unlocked, with the exception of Ness, Marth, Sonic and Snake.

The Pokemon Trainer has an unused jumping animation. Some fans have speculated he may have been playable on his own, but it seems more likely that this jumping was planned to help him traverse large areas like The Subspace Emissary.

In the Subspace Emissary mode, There is a cutscene where Ridley grabs Samus and drags her along the wall. He only lets go when Pikachu Zaps him with a Thunder bolt. This cut scene seems to have influenced a similar scene in Metriod: Other M.

In the unlockable All-Star mode, the order in which opponents are fought is based upon the order in which their game series were released chronologically, beginning with Mr. Game & Watch and ending with Captain Olimar.

Characters were originally going to visually show battle damage. You can see some of the injured player textures in the game's files.

According to Masahiro Sakurai this would have tied into a mechanic where a characters armor and other equipment would be damaged during the fight, putting them at a disadvantage.
The system was never implemented due to time constraints.

While the Project M Backroom was preparing the release for Project M Demo 2.5, a mod of Brawl that makes it play like Melee, they discovered that there was a bug in the game where button inputs can take anywhere between zero to two frames before being recognized by the game. This means that anytime you press any button in Super Smash Bros. Brawl, the attack might start up later. It is unknown why this happens.

The characters Dr. Mario, Roy, Mewtwo were supposed to make a return, and Dixie Kong, Plusle and Minun, Toon Zelda (Tetra), and Toon Sheik were supposed to appear as newcomers.

Files for these characters (sadly incomplete) can be found in the game's ISO.

Masahiro Sakurai left a picture of his cat in the ice area in the Pokemon Stadium 2 stage.

The texture of the Metroid assist trophy contains a sprite of EarthBound's Mr. Saturn. It can't be seen in-game, as it isn't mapped to the model.

The Announcer (who also voices crazy hand and master hand) is Pat Cashman, who was the announcer for "Bill Nye, The Science Guy". He even acted in some scenes in the show.