Natural gas

Natural gas is a sometimes helpful, sometimes harmful hazard that takes the form of various-colored gasses seeping from the earth through cracks in the ground or from enemies or plants. While these gasses dissipate in open-air environments, they linger in underground chambers that have no ventilation, and when inhaled, may cause various effects such as changing the properties of certain enemies, plants, and Pikmin. While natural gas in itself is not life-threatening to those that inhale it, its effects often result in dramatic changes to common strategies.

=In fanon games=

In Pikmin: Spark
Natural gas is a nonlethal hazard appearing in Pikmin: Spark, taking the form of a foggy, colored mist emitted by some enemies and plants or seeping from cracks in the ground. Normally, they simply dissipate in the atmosphere, but in underground areas such as the Cavern of Cobwebs, Rust Labyrinth, and several dens, they can quickly fill up a room and affect general gameplay. The color of natural gas determines its effects when inhaled: red gas makes Pikmin heavier, meaning they can't be thrown as high, but they and their predators are much faster; green gas makes Pikmin be able to be tossed higher, but they and their predators become slower as a result; white gas doubles the attack power of Pikmin but halves the defense of captains and enemies; lastly, purple gas doubles the defense of captains and enemies but halves the attack power of Pikmin. Natural gas can be cleared by opening vents, allowing the air to be better filtered.