Mother Mushroom is the main antagonist in the episode "Mama Said", and is the result of many smaller mushrooms fusing by unclear powers.
Mother Mushroom is a giant mushroom with a mustard yellow color on its top and a lighter yellow color on its underside. It has multiple, smaller mushrooms of varying earthy tones growing on its top. It has a hole where its stalk should be, where a tentacle is seen coming out after Finn compliments it, and has a giant eye at the end with ten long eyelashes. Mother Mushroom turns pink with a white tentacle if it's enraged.
- "The Light Cloud" (flashback, cameo)