This is an overview article which contains background information and cross-game comparisons. For game-specific information and stats, see the articles linked on the right.
“ Originally named by the descendants of those held in Chinese internment camps before the Great War, the Yao Guai is a ferocious mutated bear. ” — Fallout 4 loading screen
Yao guai are the mutated descendants of the American black bear. These vicious creatures are found in the  Capital Wasteland, the Commonwealth, the Island and Zion Canyon. They were named by the descendants of Chinese internment prisoners after the Great War.
Named by descendants of those held in Chinese internment camps before the Great War, yao guai are
mutated black bears and one of the more vicious creatures of the wasteland, sporting razor sharp claws and teeth and a nasty temperament.  Despite this, yao guai exhibit a gentle, familial bond toward one another when found together and can even be domesticated. 
Yao guai will attack nearly any other animals or people they encounter, including
deathclaws. The mutation has greatly extended their lifespan, although practical immortality has only been achieved by ghoulified yao guai, limited to remote populations on the eastern seaboard in Point Lookout and on the Island. Some of these yao guai are bears that have been born before the Great War. 
Yao guai are large, ursine animals that are descended from the bears that lived across America before the
War. Due to their zombie-like appearance, yao guai may be the bear equivalent of a ghoul, however unlike human ghouls they are not sterile, as evidenced by the presence of cubs. This is further supported by Ruzka, the only yao guai in Point Lookout, who seems to be a ghoulifed pre-War circus bear judging by the ball found in her lair and the posters around the Pilgrim's Landing boardwalk.
A common adult yao guai.
Scavengers' yao guai Edit
A tamed variant of yao guai owned by scavengers, most likely for protection and companionship.
Yao guai cub Edit
A younger specimen of the mutant bear.
Giant yao guai Edit
Larger versions of yao guai.
Stunted yao guai Edit
Shaggy yao guai Edit
Scorched yao guai Edit
Unique yao guai Edit
A unique yao guai found in its
lair in Point Lookout.
Ghost of She Edit
A unique yao guai that can be found in
Zion Canyon. She is fought under the effects of hallucinations induced by Sacred datura root tea during Rite of Passage, and appears to be a giant Yao Guai with a flaming body as well as the ability to create several copies of herself.
Son of Fluffy Edit
He is the child of Fluffy, a bear that was experimented on before the Great War by Dr. Frank. He can be encountered during
Unsolved: Tracking Terror, in the add-on Fallout 76
Behind the scenes Edit
yāo guài (妖怪) translates as "monster" or "demon." In Chinese mythology, "yao guai" are usually physical manifestations of the spirits of mistreated animals or fallen divine animals.
Yao guai captured by Enclave at Raven Rock
Yao guai in
Fallout 4 and Fallout 76
Yao guai in
Fallout 3, Point Lookout, and Honest Hearts
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