Mooshroom

Mooshrooms are Cows spawned in the Mushroom Biome, infected with red mushroom growths. They have 2 mushrooms on their body and one on their head. The player can shear them for 3-5 red mushrooms, turning them back into normal cows. If killed, they drop the same items as normal cows. Using a wooden bowl to "milk" them gives the player Mushroom Stew. Mooshrooms very rarely can be found outside of mushroom biomes.

Trivia

 * The Mooshroom's name is a portmanteau of "moo," the sound Cows make, and "mushroom."
 * Mooshrooms cannot be milked (for milk) like a normal cow.
 * Shearing a Mooshroom can result in two normal cows. One is real, the other is intangible (on SMP servers, other players cannot see the duplicate). This is most likely a bug.
 * Sometimes, when the Mooshroom is sheared underwater, the second cow is instead a Mooshroom glitching in the spot that it was sheared, somewhat like the exploded TNT glitch in multiplayer.