Background characters are minor characters in the that make cameo appearances in their corresponding home Super Smash Flash series stages, normally without interfering in the battles. As such, background characters should not be confused with stage hazards. With the severely limited stage selection of , the game only had one background character in its eight stages, but Super Smash Flash includes many background characters in its large and growing list of stages.
Super Smash Flash 2
In Super Smash Flash
Whispy Woods appears in the background. Unlike his appearance in the original , he is merely a cosmetic addition and does not blow wind.
Super Smash Bros.
In Super Smash Flash 2
A few Lumas are seen soaring around the ship.
The Luma known as Lubba can be seen in front of the steering wheel of the ship.
Lava Bubbles jump in from lava in the back of the stage.
Firebars can be seen spinning around, accompanying the Lava Bubbles.
Koopa Troopas are walking back and forth on the platforms in the background.
A Buzzy Beetle is bouncing endlessly on a spring in the background.
Pidgit can be seen flying on his magic carpet when it appears.
A flock of Mini-Neckies flies by from one side to the other.
A pair of Kritters arrive in a small boat and will blast a cannonball on the stage. The boat will sink after blasting the cannon, taking both Kritters with it as well.
The Scurvy Crew frequently appears on small islands.
Pak E. Derm is walking back and forth behind the trees.
Jimmy T. appears during the Taunt! microgame.
Tingle is carried by a balloon that can be used as an additional platform. Tingle will fall if the balloon is burst.
The Moon slowly approaches the stage as it passes through numerous changes. When it is about crash, which leads to a harmful meteor shower, the "Song of Time" is played and the Moon gets back to its original position to repeat the process.
King Dedede can be seen flying across the stage in the background, from the left side to the right.
A group of three Bronto Burts can also occasionally be seen flying in a wavy pattern in the background, from the right side to the left.
Arwings constantly fly by to eventually boost toward the horizon and disappear.
Magnemite and Beldum can be seen in the background during one of the stage transformations.
Butterfree and Moltres can occasionally be seen flying across the stage in the background.
Giygas appears all throughout the foreground and background, moving endlessly across the stage.
A sleeping Red Bulborb lies in the back of the stage.
A Cloaking Burrow-nit can also be seen left to the Red Bublorb but far behind it.
Captain Viridian is seen on the Nintendo 3DS screen during the VVVVVV game, changing the stage's gravity.
The Eggrobo can be spotted flying in the background from one side to the other.
The four ghosts — Blinky, Pinky, Inky, and Clyde — roam across the maze in the background.
A huge flock of bats are seen flying in the upper part of the stage.
The four fiends — Tiamat, the Kraken, the Lich and Marilith — float by in the background. They are rendered in still images and do not move at all other than scrolling from side to side.
Piccolo stands in the foreground witnessing the fight through the length of the match.
Vegeta, Son Gohan and Trunks fly across the stage from right to left at high speed.
Gaara is seen left to the Ichikaru Ramen Bar, bending some sand.
Itachi Uchiha teleports in to the plateau on the background, to later teleport out.
Chōji Akimichi is seen sitting at the Ramen Bar, eating a lot of ramen.
Shikamaru Nara can be seen snoozing on the Ramen Bar's rooftop.
Hinata Hyūga will occasionally lean out from the right side of the Ramen Bar.
Rock Lee is seen doing one-handed push-ups in front of Ino's flower shop.