Radioactive Luminescent Mushroom

The Radioactive Luminescent Mushroom is a common type of fungus that gives off a green glow. They are most commonly found growing in dark, underground environments. In Metro Exodus, Artyom can harvest these glowing mushrooms for chemicals to use in crafting.

Overview
These light giving mushrooms were once a very rare type of fungus that fed on radioactive materials and radiation. Like any other mushrooms of the 21st century, they grow in dark areas and can be found in most dark tunnels. The luminescent glow is a by-product of the radiation they feed on. It is possible to see green clouds surrounding the mushrooms. These clouds contain the spores of these mushrooms, and are highly radioactive and toxic when inhaled.

Origin
There were many types of luminescent fungi around the world before the war, although none of them are radioactive. In real life there are a few fungi that convert gamma radiation into energy for growth, they were first discovered around the Chernobyl nuclear disaster in 2007 as black fungus. However, unlike the mushrooms depicted in-game, they do not glow. In theory a luminescent fungi could develop this trait in the presence of large amounts of radiation, much like the environments in the post-war world of Metro 2033 and Metro: Last Light.

Tactics
The general rule for the luminescent mushrooms is to follow, but avoid them if possible. Players may sometimes find a cluster of these mushrooms blocking their path. If there is no way around them, the use of a gas mask may be recommended.

In Metro: Last Light, these mushrooms no longer give off radioactivity, so people grow them for their psychedelic effects.

Trivia

 * In Metro 2033, these mushrooms usually mark areas with high amount of radiation, and toxic air, so avoid them when possible or equip the gas mask all the time.
 * Not all mushrooms emit high amounts of radiation (they do not hurt Artyom when they come within contact) and according to dialogue between characters, some species (presumably not radioactive nor heavily mutated one) are also used as a primary food source or the ingredient for homemade vodka.
 * The mushrooms will bleed and explode if you hit them or shoot them.
 * This plant may possibly be based off of the "Russian Glowcap" mushroom from Metal Gear Solid 3.
 * A similar or perhaps even the same species of mushroom is found in parts of Kraków, Poland - as we find out in The Promised Human.
 * In Metro Exodus, these mushrooms seem to point out a more tactical or stealthier way to your intended destination.

Gallery
Radioaktiv leuchtende Pilze