Mushyrooms are a type of vegetation found in the Caves of Despair. They resemble real-world mushrooms with dark spots on their round caps. Unlike most other Ninjago wildlife, they appear to be identical to their real-world counterparts, possessing no supernatural qualities.
Ninjago.com Description
Wildlife: Vegetation
Pack your lunch, because there's little food here!
There are lots and lots of Mushyrooms in the Caves of Despair, but Mushyrooms aren't plants, they're fungus, and fungus doesn't need light to grow... it just needs animal droppings, animal bones, and slimy cave walls.