Yao guai ( Fallout 4 ) Yao guai are a species of mutated bears that inhabit the Commonwealth and Far Harbor in 2287 . Background . The name comes from the Chinese term " yao guai " ( 妖怪 ) , which translates to " monster " or " demon " . The name was given to the creature by the descendants of the Chinese that were living in internment camps during the Great War . Characteristics . Biology . The yao guai is a mutated bear of debatable origin species in the Commonwealth . Possibly mutated from the black bears native to the region , these yao guai are generally larger than their unmutated predecessors and are more aggressive . The physical build of the Commonwealth variant does not seem to drastically deviate from pre - War bears as much as the yao guai in the Capital Wasteland and Zion Canyon . Comparatively , they are overall less dog - like in their posture and movement , sport thicker patches of fur , and more body fat . Since their upper body , chest , and arms are not as massive , the Commonwealth yao guai have a more traditional bear - like posture and gait . Gameplay attributes . Although generally found alone , yao guai exhibit a gentle , familial bond toward one another when found together , provided they do not feel threatened by the observer ' s presence . Yao guai will attack nearly any other creature or person they encounter , including deathclaws . They seem to appear as often during the daytime as they do during the night time . This is a primary difference between the Commonwealth yao guai compared to the Capital Wasteland variants which are more nocturnal in nature . These creatures also have the ability to cause , unlike their Capital Wasteland counterparts , the staggering effect on every of their attacks , even if the player character is quick enough to block them . For this reason , melee fighting against yao guai might be difficult , especially with slow weapons such as the super sledge , and if fighting against a group . Attacks must be properly timed , otherwise the player character might get stuck in the stagger effect , giving yao guai enough time to strike once again . Variants . Stunted yao guai . Not as physically imposing as normal yao guai due to minor malformations , past injuries , or arrested development . As a result , they are less of a threat compared to other variants . Wherever they are found with another yao guai it is usually one with a similar affliction . Young yao guai . The young yao guai is a cut content character from " Nuka - World " . Based on the name in the editor ( DLC04POISC11 _ EncYaoGuai , ) it was planned to appear at the yao guai cave to the northwest of the Nuka - World junkyard . The young yao guai is identical in appearance to a fully grown yao guai . Pack yao guai . Found in a cage in Nuka - Town backstage , this Yao guai is kept by The Pack . Yao guai . The typical form of a yao guai , they are stronger than their stunted counterparts and can prove a difficult fight for low level player characters due to their considerable strength and aggressive nature . Yao guai ghoul . A ghoulified version of the yao guai , added to the game with the " Far Harbor " add - on . Its sensory organs seem to be heavily damaged due to radiation poisoning , age , and past injuries , as they have 7 less perception than their non - ghoulified variant . Shaggy yao guai . Larger in size with longer , more shaggy fur than the average yao guai , these variants have greater resilience and more power behind their attacks . Irradiated yao guai . This variant of yao guai was an addition included in " Far Harbor " . These yao guai are sickly green in color with hard , bony growths sprouting from their bodies , including near their eyes . Irradiated yao guai are more perceptive than their other yao guai , rendering them a capable enemy . Glowing yao guai . Similar looking to standard yao guai . However , it glows due to an excess of radiation absorbed by its body and is considerably tougher than its counterparts . Albino yao guai . These yao guai are much lighter in coloration than a typical yao guai due to a genetic defect causing albinism . They are significantly tougher than their standard counterparts . Rabid yao guai . The rabid yao guai is a yao guai that has been infected with Rabies or a similar illness . In appearance , it has red welts dominating its sides and face , giving it a diseased look . Despite its unhealthy appearance , it can prove to be a deadly adversary in combat . Dusky yao guai . The deadliest yao guai variant in the Commonwealth , it has a darker coloration compared to typical yao guai . Additionally , it has more pronounced scars on its body . Sporting a large health pool and powerful attacks , it can be an issue for the player character at any level . Those unprepared for such an encounter can meet a swift death in just a few strikes . Dusky yao guais level with the player and are therefore immune to the Animal Friend perk . Appearances . Yao guai appear in " Fallout 4 " and its add - ons " Far Harbor " and " Nuka - World " .