Poison cloud

Luigi approaching the gas.

A poison cloud is a dangerous substance found in The Cave stage of Adventure Mode: The Subspace Emissary. While inside this purple mist, fighters continuously take 2% damage every 20 frames (one-third of a second), though they do not flinch from the effect. Poison clouds also do not inflict any knockback, but the gradual damage makes the player's fighter a lot more vulnerable to enemies.

Poison clouds can be cleared temporarily by activating a nearby switch. The duration for which the poison clouds are cleared depends on the location and chosen difficulty setting.

Gallery

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  The character gets set on fire as it passes through the poison cloud without pressing the switch.

Trivia

• In some instances, if Sonic dashes through the gas wearing a Bunny Hood, he may not take damage.
• The Poison Cloud in Super Smash Bros. Ultimate's spirit battles have a similar concept to poison clouds as they are both purple gaseous substances that deals damage to the player.
  • In addition, Piranha Plant's Poison Breath could be considered a miniature version of this, as they have the same effects with the Poison Breath being much smaller.
• The gas is similar in appearance to the purple gas in Poisonous Pipeline from Donkey Kong Country 3: Dixie Kong's Double Trouble!.
• The gas is coded to be able to toggle between damaging or healing, though it is always set to deal damage.