Figure-8 Circuit

Figure-8 Circuit (, 8-Cross Circuit), originally referred to as Mario Circuit (, Mario Circuit), is a playable stage in Super Smash Bros. Brawl, and Super Smash Bros. Ultimate.

In SSB4, it was renamed to Mario Circuit (Brawl) to distinguish it from the similarly named new stage.

In Ultimate, it was renamed again to its current name to further distinguish it from the aforementioned SSB4 stage that is also in Ultimate, and due to its strong resemblance to the track of the same name from Mario Kart DS.

In Ultimate, is fought here for her unlock battle.

Stage overview
The stage has a simple layout, being a walk-off with solid ground making up the base of the stage. There are three soft platforms above it, arranged in a trapezoid shape, with the platforms on the sides being walk-offs as well.

At regular intervals, Shy Guys in go-karts will drive from the background on the lower road, similar in concept to the F-Zero-themed stages and Port Town Aero Dive. Some time later, they will fly over the platforms on the upper road from the left, though players are alerted beforehand by a flashing warning arrow, akin to Onett. If players are hit by the karts on the ground, they will take 15% damage and moderate vertical knockback, while the karts on the bridge will deal 10% damage and weak knockback. The Shy Guys can also be attacked, which will send them spinning out to the side of the screen and temporarily take them out of the race. Additionally, the screen in the background shows the location of the Shy Guys on the circuit, providing extra warning for their arrival.

Ω forms and Battlefield form
In Super Smash Bros. for Wii U, the Ω form of this stage consists of a new, raised platform in front of the standard version of the stage, which can be seen in the background. Shy Guys still race along the track but do not interfere with the fighters. Walk-offs are removed.

In Super Smash Bros. Ultimate, the Ω form and Battlefield form are similar to SSB4's Ω form; however, the stages hover above the racetrack, and they are resized and reshaped to match and, respectively. The three soft platforms of the Battlefield form somewhat resemble the soft platforms of the normal form.

Hazards Off
With stage hazards turned off in Ultimate, the Shy Guy karts do not appear. Accordingly, the screen in the background only displays the animated wallpaper, with the course map and rankings being absent. This change also affects the Battlefield and Omega forms

Origin
is the name of a track that appears in every ' game since ', but this stage's design does not resemble any Mario Circuit in particular. However, it appears to take inspiration from Super Mario Kart's, which has a jump that overlaps another part of the track. The distant, tall mushrooms and trees with faces are also taken from 's.

The overall design of this stage instead resembles in , which it is named after in Ultimate. Figure-8 Circuit features a seating area for spectators, pipes in the background, and giant block structures which originally appeared in . All these features are retained in this stage, but Figure-8 Circuit only had one seating area, while this stage features two. Additionally, the large sign which reads "Mario Circuit" (or "Mario Kart", in Ultimate) is designed similarly to signs that appear throughout Figure-8 Circuit.

Mario Kart DS and  feature Download Play, which allows players who do not own the game to participate in local multiplayer, though they will only be able to race as a Shy Guy. This stage includes Shy Guys as racers, which could be a reference to this feature.

The design of the giant screen in the background is based on the map that was displayed on the Touch Screen during races in Mario Kart DS. Pressing the "Y" button or tapping the screen with the stylus gave the player this view, along with the location and position of every racer. All of these features are retained here, though the motif of the cup the race is a part of is replaced with a Smash logo motif.

Tournament legality
Mario Circuit is banned in tournaments due to its walk-off blast lines, which, in Brawl, allow chain-grabbers to chain throw an opponent off of the stage's sides. In addition, the karts are overly powerful stage hazards, and gameplay centers around avoiding the karts, as well as throwing opponents into them.

Glitch
While using or 's Triforce Slashes, if a Shy Guy is hit by the final strike and only the final strike of the Final Smash, the Shy Guy will continue to go around the circuit, but it will be in slow motion. It will still show the kart's position on the monitor in the background but it will be far behind the group. Even though it is moving so slow, it will still deal normal damage and knockback.

Update history
 1.0.2

Trivia

 * This was the last stage that was first shown in trailers to be confirmed on the DOJO!!. Over a year had passed since its initial revelation, making Mario Circuit the stage with the longest duration between its trailer and DOJO!! confirmations.
 * In the trailer that originally revealed Mario Circuit, the Shy Guys were all driving white karts and the screen in the background was blank.
 * Some items and Final Smashes can't affect the karts on the track.
 * When Iceberg is used, for example, the karts will simply drive straight through the ice.
 * If 's Puff Up is used, karts will go through Jigglypuff while it's expanding (though shrinking could still wipe them out).
 * Cook Kirby also doesn't have any effect on them; this is because they are obstacles.
 * They are also unaffected by Bumpers.
 * If Andross is summoned from an Assist Trophy, the lower part of his face will be below ground.
 * In Brawl, if a song directly from any Mario Kart game is playing on this stage, it will only begin playing after the pre-match timer is finished, just like in a standard Mario Kart race.
 * As pointed out on the DOJO!!, the entire track is present, despite most of it not being viewable, even when pausing and changing the camera angle. However, it can be viewed by hacking.
 * POW Blocks are able to hit Shy Guys that are behind the stage.
 * In SSB4, this is the only stage to have something other than "64" in parentheses in its name.
 * In Ultimate, Color TV-Game 15 and Devil can only be summoned from an Assist Trophy on the Battlefield and Omega forms of this stage. Additionally, Abra and Marshadow can only be summoned from Poké Balls on the stage's Battlefield and Omega forms.
 * In the files of Ultimate, the stage is referred to as "Kart_CircuitX".
 * Shy Guys do not race on the stage when hazards are off, even in Battlefield/Ω form. This makes Figure-8 Circuit’s Battlefield and Ω variants one of two stages where the Battlefield and Ω variants have differences between hazards on and hazardless versions, the other being Hollow Bastion (where the stage’s Battlefield/Ω forms do not transform into Dive of the Heart when hazards are off).