Fallout: Equestria Wiki
Boo sitting and staring
~ DAfavicon.png MisterMech
Race Blank
Sex Mare
Faction/Role Blackjack's group

Boo is a Blank pony mare, who was discovered living in the lower levels of the Hippocratic Research laboratories during Blackjack's assault on Project Chimera. She is one of the main characters in Project Horizons. Boo is introduced in Chapter 38.


After the War

Boo was recently created by the machines beneath Hippocratic Research, specifically the Tree of Life used to create Blank Ponies for organ harvesting and testing in Project Chimera. Boo lived in the lower levels, scavenging for food alongside her fellow Blanks. Unlike the others who did not understand the concept of danger, she exhibited heightened self-preservation instincts and has survived much longer than many other Blanks, as evidenced by her skinnier frame from lack of nutrition and longer mane and tail hair.

Recent History

Boo was first discovered by Blackjack in an old canteen under Hippocratic Research, who mistook her for a ghost due to her entirely white body. Boo didn't respond to Blackjack's speech and, when offered a snack cake, couldn't perform basic tasks such as removing a food wrapper. Her first emotional response was to begin crying when Sanguine's henchpony Fury arrived in the room and attempted to kill them, the Pheonix-fused monsterpony not understanding why Blackjack would defend a worthless 'Blank'.

After defeating Fury, Boo returned to trying to find food, though Blackjack brought her along with her, feeding her cakes on occasion. Boo proved to be a valuable companion to Blackjack as her heightened survival instincts and senses allowed her to detect danger before they encountered it.

Boo kept close to Blackjack at all times, Blackjack being forced to carry her at one point through a stairway full of Flux. She later used a pistol to kill a unicorn attacking Blackjack, though her eyes were Blank at the time and it looked like she was trying to swallow the gun, suggesting it was dumb luck that she killed the attacker.

Boo would leave Hippocratic Research alongside Blackjack and followed her to the Fluttershy medical centre where the team reunited. She exhibited a docile and primitive nature, frequently taking naps, wetting herself in a corridor and continuing to prove incapable of understanding speech. She was left with the rest of Blackjack's friends when she took off, leading the Harbingers away from the team as they made their way to Chapel. During the three days that Blackjack was gone, P-21 noted that Boo was wondering around Chapel, trying to find the missing Cyber-unicorn.

Boo was later reunited with Blackjack in Chapel, continuing to act as a docile mascot of sorts. Lacunae speculated that she most likely does not possess a soul due to her nature as a clone, however Blackjack wishes to believe that she is a real pony, just not an educated one. She began to show greater signs of sentience, as evidenced by her openingFancy Buck Cake wrappers on her own, assisting Scotch Tape with packing bags and following simple instructions. She also appears to be blessed with a great amount of luck, as hostiles will typically suffer great (and sometimes comical) misfortune when she is around.

After Boo shows signs of increasing anxiety and sadness when separated from Blackjack, the team begin taking the Blank on their adventures where she continues to prove useful, even if not so much in combat. In the Society's headquarters at Elysium, she continued to stay close to Blackjack after being foalnapped alongside Scotch Tape. Interestingly, during a conversation Blackjack had with the Dealer, Boo's reactions and body language hint that she may be capable of perceiving the ghostly figure. She wore a cake-themed dress acquired by Lacunae to the Society's Gala and was mistaken for a baroness, becoming the star of sophisticated conversation despite her inability to speak.

In Shadowbolt Tower, following an unwelcome upgrade to her augmentations, Blackjack suffers a mental breakdown that threatens to see her go on a mindless rampage; she is only stopped when Boo recognizes her and treats her with her usual level of affection. it is at this moment that she says her first word, "Bwackjack", which gives Blackjack the stability she needs to press on.

Following the events of Shadowbolt Tower, Blackjack and Boo become trapped alone in the Hoofington Core for 3 months near the wreckage of a downed Raptor until they are finally located by Rampage. It is during this time of isolation and hiding that Blackjack teaches Boo to speak, allowing her to hold conversations in a child-like manner. Blackjack also speculates that her origin as a flux created Blank gives her immunity to the deadly levels of enervation in the core.

During an attack by the Legate, it has been revealed that Discord had been hiding within Boo's mind since the destruction of Project Chimera, seeking protection from Blackjack and subtly nudging events around her. This not only explains how she is able to survive around Blackjack and not melt in extreme enervation fields but may also explain how she could live off snack cakes and NOTHING else. Discord notes that Boo is unique for a Blank as she appears to be slowly building her own soul and may one day become a spirit of chaos much like himself (though Boo expresses a desire to be kind, following Blackjack's example). He also notes that Boo is capable of seeing things similarly to how he does, which explains her near precognitive abilities and gift for seeing through rouses. Discord is able to override her personality at will, causing his one fang to emerge and changing her eyes to match his, though the two are capable of having conversations with one another.

Knowing what will happen ahead of time, Discord had Boo sneak away under the Robronco headquarters while he left to interfere with Blackjack and Cognitum's confrontation, ensuring Blackjack's survival at the hooves of Steel Rain. Following Discord's instructions, she retrieved Blackjack's discarded gear and escaped the core (seemingly by herself), later reuniting with Glory, P-21 and Scotch Tape in Chapel. There, she uses her innate ability to see through rouses to confirm the identity of the real Blackjack (now a Blank/Clone, not unlike herself), when none of her friends would believe her. She also assisted in a larger demonstration by Triage that Blackjack was truly a Blank by demonstrating her resistance to Taint.

Two hundred years later, Boo is still around and has become the new Spirit of Chaos after Discord's death. She hangs around with Blackjack and Littlepip on occasion, and wear's Rainbow Dash's old Mare-Do-Well power armor.


Like all non-cloned Blanks, she lacks a cutie-mark and her coat and mane are pure white, showing no signs of pigment, with eyes so pale that it is difficult to tell where the sclera begin and end. Unlike the other Blanks found under Hippocratic Research, her mane and tail are rather long and she shows signs of starvation, hinting that she has survived longer that the others. Despite a long-running fear of being strapped into armour, she is eventually coaxed into wearing Psalm's black operative barding, causing her to be confused for Blackjack by those unaware of the Cyber-unicorn's most recent augmentations.


When she is first found, Boo shows little more than instinctual reactions to happenings around her (which is still considered unusually advanced for a Blank); she shows fear at the sound of strange noises and a dislike of being confined, to the point of outright panicking during attempts to garb her in armour.

Overtime Boo begins showing signs of an emerging, childlike personality; aside from her gleeful reaction to snack cakes, she starts picking up habits from Blackjack (such as shoulder-bumping ponies after watching Blackjack and Morning Glory do it) and playing with Scotch Tape. She shows a great attachment to Blackjack and becomes noticeably upset and anxious whenever they are separated. After joining the team on missions she begins to show a greater understanding of others and social reactions, such as reacting with embarrassment at Blackjack masturbating after her encounter with Lancer, and comically acting haughty around a group of aristoponies at the Society's Gala. Recently she shown a slightly more manipulative side when she "weaponised her cuteness" to guilt a pony into giving her a plate of snack cakes

She shows signs of being highly precognizant and perceptive, reacting with fear and ear twitches when danger is imminent and (after gaining a greater understanding of the world around her) taking action to prevent bad things from happening; examples of this include the times she has used her astounding luck to maneuver around enemies so they would suffer accidental misfortune, the time she saved Lancer's life by frantically placing a hat on his head to foil the aim of a sniper, and her seemingly near-suicidal jump from a Raptor, allowing her to save Blackjack from falling through the cloud layer moments later. How much of this is due to Discord's influence is unknown, however she continued to exhibit these skills even when he was not around.

After learning how to speak with Blackjack's help, she becomes an avid conversationalist and shows a great sense of compassion for others, along with a somewhat happy-go-lucky mentality.


Blackjack - Having been befriended by Blackjack through the use of snack cakes, Boo seeks to stay close to Blackjack whenever possible, becoming nervous and upset when she is not around. Blackjack (despite the assertions of others) believes that Boo is a real pony with a soul and watches her growing personality with great interest.

Scotch Tape - Boo frequently plays with and assists Scotch Tape when they are together, showing her developing knowledge of simple tasks.

Discord - Boo reveals that she has been aware of Discord for some time, however she kept it a secret at his request. Boo is curious about Discord and has innocently asked him a number of questions about his past while the two were able to talk to one another.


  • She is smarter and appears older than regular Blanks and has excellent survival instincts
  • She also appears to have heightened senses, often detecting danger before it is visible. She was shown detecting danger outside of Blackjack's Pipbuck's EFS range
  • She behaves more like a pet than a pony; she isn't house trained, evidenced when she urinated in the hospital halls at the Fluttershy Medical Clinic
  • She was seen drinking out a toilet in Megamart
  • She doesn't like wearing body armor, though eventually accepts being dressed in Psalm's old operative armor; she has been mistaken for Blackjack on more than one occasion when wearing this, due to Blackjack's own radical changes in a appearance
  • She is fond of Snack Cakes
  • She is very attached to Blackjack, so much so that her first word was "Bwackjack". She has since learned to speak at a children's level under Blackjack's tuition.
  • She once operated a gun, though it was probably unintentional
  • She is the secret host of the Spirit of Chaos and Disharmony
  • She was mistaken for a Baroness at the Society's Gala
  • She can be healed by pure Taint (I.M.P), though may be vulnerable to mutation by raw Flux like other Blanks.

Boo in Other Side Fics