Door

A standard red door.

Doors are found in the Subspace Emissary to teleport the player into another room. Doors are usually red in color with a pointy top, with blue light shining out from the edges.

Doors act as a checkpoint in the Subspace Emissary. When the player runs out of stocks (i.e. game over) and continues, he/she will appear next to the door that the player had last entered.

Doors also help increase the player's clear percentage. All the doors in all the levels must be entered.

Red doors reappear in the Smash Run mode of Super Smash Bros. for Nintendo 3DS. In this mode, they usually lead to challenge rooms where players can attempt a timed challenge for additional power-ups. Other times, they may lead to bonus rooms, with stat boosts or treasure chests available. Food or Iridescent Glint Beetles may also appear.

Types of doors

While the doors are usually red, there are different types of doors as well. In the stages in the Halberd, the doors are bronze in color, and slide open instead of opening from the middle. In the stages which feature the Research Facility and the Subspace Bomb Factory (i.e. the Isle of the Ancients), the doors are gray in color with black stripes. In the Subspace stages, the doors will open like the red ones but are purple and have what appear to be scales on it.

In some stages, the end of the level is illuminated by rays of light. Entering the light will make it brighten until the screen goes back, at which point the regular finish screen appears. If the stage is completed again, the light will be replaced by a golden door.

In The Great Maze, doors with black smoke emerging from the edges indicate that there will be a Subspace Clone/Boss behind the door. Also in the Great Maze, there are orange doors with a yellow circle in the middle which lead to save points.

In one room in the Great Maze, there is a large purple door which leads to Tabuu's Residence.

Day-changing doors

In The Lake, there are day-changing doors that are yellow or sky blue, with a triangle in the middle of it. When a player enters that kind of door, they will be teleported into a similar world, but are different in some minor ways, but the most noticeable is the background. One of the areas is during the day, and the other is during the evening. The members of the Subspace Army are different as well. What a player does in one world affects what happens in the other. It is likely that going through one of these doors will transport you forward and backward in time, depending on the color.

There are also day-changing doors in The Great Maze, in an original area based loosely on The Forest.

Triple switch doors

In the Subspace Bomb Factory, there is a locked metal door with three lights on it. In the area, there are three switches (blue, red, and green) throughout the section that look like levers. Hitting one will make the light of the same color as the switch shine, and sending a beam of the color down to the three-light door. Once the three switches have been activated, the three lights as well as the edge of the door will shine and the player will be able to pass.

There is also a triple switch door in The Great Maze, in an original area of The Research Facility. This door functions identically to the previous one, except that the door itself is shrouded in dark mist, indicating a Boss Battle. However, the three switches needed to open it are found in three different interconnecting rooms of the great maze, instead of all being in different parts of one big room.

Hidden doors

Hidden doors are doors that are not necessary to enter to clear a level. For example, a door might only appear right after it has been passed by, a switch must be pressed to make the door appear, or it is hidden in an unexpected place, such as where an arrow hints to go down, while the hidden door is actually above.

When a hidden door is entered, it will usually lead into a small room with a Turquoise Cube, and an Orange Cube which is harder to reach. The Orange Cube is also necessary for a higher clear %.

Special doors

There are three special doors which only appear after the Subspace Emissary has been completed. Those three doors can be found in The Swamp, The Forest, and the The Ruins. When they are entered, there will be three challengers that have not appeared in the Story Mode: Jigglypuff, Toon Link, and Wolf, respectively. Defeating these characters will make them join the party and the player will unlock them, if they're not unlocked already.

Trivia

• When a fighter enters a door, they are respawned from scratch as if a new match has started. As a result, they lose all status effects, held items, and special move statuses, and Olimar will have three new Pikmin.
• When a fighter enters a door on the ground, they will walk into it. However, when fighters enter a door that is in midair, they will tumble toward it. This animation is the same as being Footstool Jumped off of.
• Through hacks, it is possible to play as Giga Bowser in the Subspace Emissary, revealing that he is incapable of using doors. As a result, without a partner to traverse doors for him, Giga Bowser can only complete levels that lack doors, those being Midair Stadium, The Ruined Hall, Battleship Halberd Bridge, and The Canyon.
• There are also two areas in the Subspace Emissary that are entered without doors. In The Ruined Zoo, the player enters what appears to be the entrance to an abandoned aquarium, and in The Lake Shore, they enter a cave through a large opening.

Gallery

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  A door found inside the Isle of the Ancients.

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  A door found in the Halberd.

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  A door found in Subspace.

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  Door leading to Tabuu's Residence.

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  An orange day-changing door.

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  A door leading to a save point in the Great Maze.

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  A gold door found at the end of a stage in the Subspace Emissary

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  A gold door found at the end of a stage in Subspace

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  An opening that functions as a door in The Ruined Zoo

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  An opening that functions as a door in The Lake Shore

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  An inactive triple switch door.

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  A triple switch door with all three switches activated.

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  A shadow bugged-triple switch door at the Great Maze.

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  An unactivated switch for a triple switch door.

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  A switch for a triple switch door being activated.

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  An activated switch for a triple switch door.

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  A shadow bug door at the Great Maze.

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  Lucina encounters a door in Super Smash Bros. 4's Smash Run.