Amanita ocreata, commonly known as one of the many destroying angels, or more precisely the western North American destroying angel, is a deadly poisonous basidiomycete fungus, one of many in the genus Amanita. The large fruiting bodies (the mushrooms) generally appear in spring; the cap may be white or ochre and often develops a brownish centre, while the stipe, ring, gill and volva are all white. A. ocreata resembles several edible species commonly consumed by humans, increasing the risk of accidental poisoning. Mature fruiting bodies can be confused with the edible A. velosa (springtime amanita), A. lanei or Volvopluteus gloiocephalus, while immature specimens may be difficult to distinguish from edible Agaricus mushrooms or puffballs.

The species occurs in the Pacific Northwest and California Floristic Provinces of North America, associating with oak trees. Similar in toxicity to the death cap (A. phalloides) and destroying angels of Europe (A. virosa) and eastern North America (A. bisporigera), it is a potentially deadly fungus responsible for several poisonings in California. Its principal toxic constituent, α-Amanitin, damages the liver and kidneys, often fatally, and has no known antidote, though silybin and N-acetylcysteine show promise. The initial symptoms are gastrointestinal and include abdominal pain, diarrhea and vomiting. These subside temporarily after 2–3 days, though ongoing damage to internal organs during this time is common; symptoms of jaundice, diarrhea, delirium, seizures, and coma may follow with death from liver failure 6–16 days post ingestion.

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