Stage hazard

A stage hazard is any aspect of a stage which could pose a threat to players. Most stage hazards deal damage and knockback, although a few involve sudden movements of the stage or a panning camera that can carry a character into the blast line. Less agile characters are especially vulnerable to camera panning. A stage hazard is not to be mistaken for any aspect of a stage which might aid or save the opponent, such as the Support Ghost in Yoshi's Island, although it may play several roles.

How predictable a stage hazard is and how much influence it has over the match are factors usually considered when deciding stage legality. Stages with many or overwhelming hazards are typically banned in tournaments as they tend to interfere with the outcomes of matches or because the competitors only prefer aspects of a match that they have control over.

Some stage hazards may be extremely minute or subtle, or only apply to certain characters; For example, the balloon in Smashville may unexpectedly collide with Ness's PK Thunder, making him temporarily vulnerable or leaving him in the helpless state if he is in the air.

Types of stage hazards

• Static hazards generally stay in place or follow a set path and produce damage and knockback upon collision. Examples of stationary static hazards include spikes and the bumpers on Peach's Castle, and an example of a moving static hazard includes the minecart in PictoChat. Some static hazards have a fixed knockback.
• Launcher hazards will quickly move the character from one part of the stage to another and sometimes into the blast line. The most basic example of a launcher is the catapult on Pirate Ship which will only fling the victim to the far left of the pirate ship. The Barrel Cannon in Congo Jungle is considered a launcher but not usually a hazard because there is a brief period of time where the player has control over when it will fire.
• Rogue platforms are platforms that travel or move suddenly move through a blast line. For example, if a character is stunned while standing on an Arwing in Sector Z, the Arwing may leave the scene and carry the character into the blast line. The track on Big Blue may also be considered a rogue platform.
• Transformation hazards create a situation where the character can be caught under or off to the side of a stage because of a sudden shift in the stage. For example, the Frigate Orpheon stage can cause players to accidentally self-destruct when it flips upside down. Not to be confused with the trapdoor hazard, as transformation hazards specifically feature a (near) global change in the stage.
• Lava hazards, which do not specifically need to be lava, are a part of a stage that in abundance rises up or pours in while covering a blast line. Collision with the lava will result in damage and knockback. In high hitstun and low percentage environments, characters will sometimes bounce around in rising lava. The original stage to feature a lava hazard is Planet Zebes in the form of acid.
• Predator will pursue the players and attack them. Some examples include Arwings which fly and in and fire lasers around characters on various Star Fox stages and the Combo Cannon on Halberd.
• Trapdoor are a part of a stage that can give way and reappear over a character, which usually makes returning to the stage difficult or impossible. For example, King Bulblin on the Bridge of Eldin can destroy the bridge and players can be trapped below it when the bridge is later reconstructed. Another example of a trapdoor hazard is the Drop Block in one of the default custom stages in Brawl.
• Vehicles may occasionally speed through some stages, causing damage and knockback to characters that collide with them. A warning that a vehicle is approaching is usually given, such as on Onett, or the vehicle can be seen from far away before arrival, such as the racers in Mario Circuit. Vehicles collisions may also trigger explosions on certain items.
• Weather hazards affect physics. These hazards typically follow a change in scenery or a stage transformation; For example, the Flying transformation in Pokémon Stadium 2 introduces a weather hazard that blows gusts of wind upwards. Characters caught in the gusts have a dramatically reduced falling speed and are easier to Star KO and approach. Other weather hazards may affect the progression of time, such as Dialga in Spear Pillar.
• Slippery platforms make it difficult to control the momentum of traversing characters. Slippery platforms may also increase the odds a character will trip. This hazard does not affect the Ice Climbers.
• Panning cameras force characters to follow the camera as blast lines will move with the camera. Icicle Mountain features a camera that pans up the stage at varying speeds, which can catch characters with the lower blast line if they have poor jumping ability.
• Obstacles generally obstruct character movement or present a challenging gap to cross. While not dangerous by themselves, obstacles are often used in conjunction with panning cameras.
• Enemies generally appear as a species and can obstruct the player or cause knockback and damage. Enemies are similar to static hazards, with the exception that most enemies can be defeated or can be grabbed and thrown. One example of an enemy hazard is the Polar Bear in Icicle Mountain.
• Monsters are large species that cannot be defeated and can usually instantly KO a player when hit or grabbed by. Some monsters include the Ultimate Chimera on New Pork City and the fish on Summit.