Holding down L before selecting the Dream Land stage in the 3DS version will cause the stage colors to change to black and white, instead of the usual black and green.

The Pokemon Trainer trophy makes reference to the first opening theme music from the English dub of the Pokémon anime.

"Pop quiz! What do Misty, Brock, Cynthia, Iris, and Ash all have in common? That's right"”they're all Pokémon Trainers! This Pokémon Master in the making is the same. Back in Super Smash Bros. Brawl, he fought to be the very best"”like no one ever was. To smash them was his real test"”to launch them was his cause!"

The song that plays on the results screen after a fight is the character select theme from the first Super Smash Bros.

Sometimes when Luigi uses the green missile and he hits a wall, he will stick to the wall.

Within the game's data are a number of unused images that would have been displayed in the game's tutorial section.

According to Masahiro Sakurai, the reason the Ice Climbers were cut from the roster is because of 3DS hardware limitations. He also states that he didn't want to add them exclusively to the Wii U roster to avoid there being considerable differences between the two versions.

According to series director Masahiro Sakurai, Dr. Mario, Dark Pit and Lucina were originally considered to be alternate costumes for Mario, Pit and Marth respectively, but were eventually changed to be their own separate characters with slight differences in their movesets from the three.

All of the characters in the game were chosen at the start of development. This means Geninja was chosen before Pokemon X & Y was released, and that its inclusion was not because of its popularity.

There was an open slot for a new Pokémon character, and the team began discussing who to put in it, eventually settling on Greninja. All the reference material they had for Greninja were simply drawings at that point. Sakurai went home the same day he received the Greninja reference material and stayed up until midnight to do the motion capture for the character.

The Smash Run mode was influenced by the City Trial mode in Kirby Air Ride.

When either of the Links are fighting, the Toon Link driving the Spirit Train is replaced with Alfonzo.

The Japanese trailer introducing Mega Man in Super Smash Bros. for 3DS and Wii U has "Clash Man" (the original Japanese name) instead of "Crash Man" (the English name) in the Japanese commercial, despite being changed to Crash Man in Japan.

When the track "Wrath of the Reset Bomb" is played while on the Reset Bomb Forest, it will actually sync with what is happening on the stage, and as a result, pausing the game will stop the track. This does not happen on the the Omega variant of the stage, nor does it occur at all in Super Smash Bros. Ultimate.

The texture for the Skull Kid assist trophy contains an unused portion which seems to be the flute he used in Ocarina of Time and Majora's Mask. It is unknown what it could have been used for, though it's likley he was supposed to use it in some way when the player summons him.

If the player reflects the Starman enemy's projectile, the "SMAAAASH!!" graphic from EarthBound will flash and the starman will be instantly killed.

The game originally had a 4th set of custom moves for all characters. By hacking the game it is possible to activate them, although most of the moves are unfinished, and do not deliver damage.

In Super Smash Bros for 3DS the trophy titled "Luigi (With Poltergust 3000)" is actually wrong. The Poltergust that Luigi is wearing is actually the Poltergust 5000 from Luigi's Mansion: Dark Moon, which can be noted by the green light on the back of it.

This is the first time both Master Hand and Crazy Hand have in-game announcer calls that are used.

Kongo Jungle is the only past stage from the original game to return, with the exception of DLC.

This is the only game in which Kirby doesn't have a new dash attack, but instead reuses the one from Super Smash Bros. Brawl.

According to Masahiro Sakurai, Bowser Jr. was very close to not being included in the game's roster.