Nightkin The nightkin were an elite warrior caste in the Master ' s super mutant army and the apex of his creation of super mutants . When the Master ' s super mutant army was defeated in 2162 , many began wandering the Wasteland or banded together into groups of varying sizes and with varying ends . In 2281 , many are now either with Tabitha , Marcus , or Davison , with the last group desperately searching for more . Overview . They are superior to their fellow super mutants in terms of both intellect and skill , as the FEV - II dipping has not damaged their intelligence . While in the Master ' s Army , they had access to superior weapons and armor , including the use of Stealth Boy s . Prolonged use of these devices led to a permanent alteration of the pigment in their skin . Instead of the usual dull green , their skin is pale blue in color . The nightkin often use their equipped Stealth Boys to sneak - attack those who cross their path , remaining invisible until they come out and fight , sometimes even remaining invisible then . However , prolonged use of Stealth Boys has damaged their sanity , with them becoming incredibly aggressive , paranoid , and in some cases severely delusional . As Marcus explains , they " hate to be seen . " The cause of their paranoia is schizophrenia developed from constant use of the Stealth Boys , because of this they can become angered when stared at for a long period of time . Background . " Fallout " . Nightkin can be found in the upper levels of the Cathedral , as well as inside the Mariposa Military Base , and in random patrol encounters in the cells around the base . After the Master ' s fall , many surviving Unity super mutants had become a chaotic wasteland wandering force , set on to destroy everything it encountered . They are superior to other super mutants in skill , equipment , and weaponry . Many of the nightkin are equipped with cloaking devices , such as Stealth Boys . The only gaming effect of this is to give them a slight ethereal look , as it does not affect the player ' s chance of hitting them . " Fallout : Brotherhood of Steel " . After the death of the Master , parts of the super mutant army gathered and formed a new faction , led by Attis . Many years after their regrouping , these mutants captured the Secret Vault in order to use the FEV reserves stored inside . Attis ' goal was to continue the Master ' s plan . His army had an elite unit of nightkin , much improved in skill , and equipped with high - tech stealth suits to enhance their abilities . These suits served the same function as Stealth Boys . These suits probably originated from , or were made in the Secret Vault . " Fallout : New Vegas " . Some of the nightkin appear in the Mojave Wasteland , very often suffering from severe psychological damage , caused by prolonged Stealth Boy use . They wear the same clothes as regular super mutants , but many of them also wear hoods , and stop signs strapped to their forearms as makeshift shields . They are often found wielding rebar club s , , incinerator s , or , in the case of , bumper sword s . They are slightly more articulate in their speech , and are believed to be a stronger and more intelligent version of first generation super mutants , according to Black Mountain Radio . They are weaker than standard super mutants , however , as a result of their use of Stealth Boys . There are some scattered in the wasteland , in places such as Black Rock cave . Those nightkin under the banner of Tabitha harbor an " isolationist " ideology , openly warning humans to stay away from Black Mountain , and even commenting on the dangers of " the dreaded battle cattle " and " two - headed bear people , " a reference to the animal mascots on the flags of Caesar ' s Legion and the New California Republic , respectively . A nightkin camping on the outskirts of Novac kills one of Dusty McBride ' s brahmin every night around midnight , mistaking the message entirely . He can be found during the day , cloaked behind a boulder across the road and to the west of town . Here , he can be heard complaining about his constant insomnia and trying to silence noises in his head that he believes come from the brahmin . Despite their phobia , some nightkin have become Antlerists , and take orders from their god , Antler , an inanimate brahmin skull located in the basement of the REPCONN test site . The , Lily , is a nightkin and a former soldier in the Master ' s army . Nightkin play an important part in the quest Come Fly With Me . The Courier is sent by Jason Bright , the founder of the Bright Brotherhood , to take care of " demons " that are infesting the basement level of the REPCONN rocket testing facility . Similar to the super mutants in " Fallout 3 " , nightkin will attack ghoul s . At Brooks Tumbleweed Ranch a nightkin will appear next to the Courier and start a chat . He will offer to sell them wind - brahmin for all their . If the offer is declined , he will turn hostile and proceed to attack . Originally , if the Courier accepts the offer without asking about the price , no caps will be removed , and the nightkin will give a free Stealth Boy instead . Another Stealth Boy will be in his inventory available for pick - pocketing . However , with the game patch as of July 7 – 8 , 2011 , the nightkin will no longer give a Stealth Boy upon agreeing without question , and will take all caps . The nightkin will only have one Stealth Boy that can be pickpocketed or looted from his body . Another nightkin , Dog and his " human " personality God , appears in the add - on " Dead Money " . Although he does not use Stealth Boys , he is still a formidable fighter . Appearances . The nightkin appear in " Fallout " in the Cathedral and the Mariposa Military Base , in " Fallout 2 " as a hostile encounter on the world map , in the Secret Vault in " " , and make a comeback in " " and the add - on " Dead Money " .