Bill Cipher

Bill Cipher is a dream demon and the main antagonist from the animated TV series Gravity Falls. He appears to be a two-dimensional creature resembling the Eye of Providence symbol, only wearing a top hat and bowtie. Bill is a sinister entity that originates from the 2nd Dimension, a world that he describes as "flat" in every sense of the word. He delights in causing chaos and mayhem and seeks to spread his pandemonium to Earth.

Early history
Trillions of years prior to the events of the series, Bill originated from the 2nd Dimension. However, Bill despises living in the dimension, describing it as a "flat world with flat minds and flat ideas". He favoured chaos and destruction over anything else, and made it his mission to spread it as far as it could go. Bill "liberated" his dimension by taking to a higher plane of existence, the 3rd Dimension. He has no corporeal form, and so could only access the minds of the dimension's beings. He came to learn of a prophecy that stated he could bring his chaos into the alternate universe, and Bill manipulated countless humans over the eons to find a way into the Third Dimension as a physical being to "liberate" that dimension as well. Among his targets were Natives who lived in what would become a town called Gravity Falls, Oregon. The people discovered that Bill was too dangerous and found a way to temporarily defeat him using a zodiac with ten symbols. The people left behind a painting of their encounter with the demon, including how to summon him, and more importantly, a warning never to read it.

One day in the late twentieth century, a young man named Stanford Pines came to investigate a mysterious town in the same location where the Natives had encountered the demon. Ford discovered countless anomalies and secrets in Gravity Falls, but eventually hit a stumbling point in his research and became desperate for more answers. Bill recognized that Ford's brilliant but cocky and insecure nature and near-friendless background made him an ideal pawn. When Ford accidentally stumbled into a strange cave, he discovered the painting about a "being with answers". Desparate and naïve, Ford ignored the warnings and read the summoning inscription, but was confused when nothing happened. Later that day, while taking a nap, Bill entered the man's dreams. Bill deceived the man, telling him that he was a muse who chose one incredible person every hundred years to inspire. He told Ford that if he sided with Bill, they would unlock the greatest riddles in existence. Blinded by this flattery, Ford believed Bill to be a friend and agreed to the deal.

Ford seemed to idolize Bill and decorated his home with various images of him and a similar symbol, the Eye of Providence, which can be seen scattered across Gravity Falls. Once Cipher had tricked Ford into befriending him, he told him to build a great machine which he claimed would create knowledge to benefit all mankind. However, when the time came to test it, one of Ford's human friends, Fiddleford McGucket, was sucked into the machine and discovered its true nature: a portal into Bill's world that would allow the demon to bring his chaos into their universe. Horrified and betrayed, Ford shut down the project and hid the instructions on how to operate it. Bill, however, could not be so easily deterred and has been patiently biding his time for the portal to reactivate.

Bill and the symbol he's based on, the Eye of Providence, appear frequently in Gravity Falls. He was the unseen creator of the cryptograms in the online game Rumble's Revenge. His name and existence is deduced by taking all the capital letters in the cryptograms from Rumble's Revenge, to form the message: "MY NAME IS BILL."

Events of Gravity Falls
Bill Cipher first appears in the first season episode "Dreamscaperers" when he is summoned by the vengeful Gideon Gleeful. L'il Gideon looks up Bill in the No.2 Journal he has in his possession and performs the incantation needed to summon the wily demon. Gideon is determined to steal the Mystery Shack away from Stanley Pines (who at the time had taken his missing brother's name) and he commands Bill to enter Stan's mind in order to find the passcode to Stan's safe, which contains the deed to the shack.

Bill enters Stan's mind, but Dipper, Mabel and Soos witness Gideon's summoning and manage to find a way to follow Bill into Stan's dreamscape. Once inside Stan's head, Bill confronts the trio, and brags that he knows what they're all thinking. He tricks Mabel and Soos into looking for the memory of Stan's safe combination first, knowing they'd lead him straight to it. At some point Soos is separated from everyone else, and Bill takes his place. Once they find the correct memory he takes it and nearly escapes with it. But while he reads the combination out loud to Gideon (to whom he was connected), Mabel shoots the memory door into another memory of a bottomless pit with a nyarf dart. Gideon breaks off their deal, to Bill's fury. Bill turns his anger toward Mabel and Soos by bringing their nightmares to life. Dipper returns in a timely manner and tells Mabel and Soos that while they are in Stan's mindscape they can do whatever they want. They battle Bill and he is nearly defeated. And just as though it seems he will be forced out of Stan's head, he puts a stop to everything instead. Impressed, he decides to let them go, and after warning them of a mysterious darkness that will change everything they care about, he tells them that he'll be watching them. He leaves in a wheel almost identical to the one that appears in his entry in Journal 2.

Bill reappears again in "Sock Opera" for the first time in Season 2, when Dipper is trying to figure out the password for the laptop from "Into the Bunker". He offers the laptop's password in return for a favour he wants, but Dipper refuses the offer. Later, at the moment the laptop is on countdown for complete data erase after too many failed password entries, he appears again and Dipper accepts the deal of trading a puppet to obtain the password. Bill takes over Dipper's body as his "puppet" and destroys the laptop. He then follows Mabel to her puppet show in pursuit of Dipper's journal that is being used as a prop in the show. After Mabel has been informed of Dipper's body having been stolen by him, he finds her with the journal as she is retrieving it for Dipper. He almost swindles her out of it but ends up in a fight with her. He ends up losing because Mabel uses Dipper's physical weakness and exhaustion to her advantage. As he collapses, he is thrust out of Dipper's body. Bill possesses the Dipper puppet afterwards and says that he will return. However, Mabel lights the pyrotechnics, which destroy the puppets.

Over the following episodes, Grunkle Stan succeeds in reactivating the portal hidden beneath the Mystery Shack, bringing his twin brother Ford back home. After returning to Earth, Ford gets to know Dipper and shares many of the secrets he learned on his inter-dimensional travels. He also tells Dipper about the pact he had once made with Bill, showing him a small dimensional rift contained within a snowglobe-shaped vessel. Ford warns Dipper that if the rift were to be breached and open completely, Bill would be able to manifest physically in the 3rd Dimension and would bring about the end of the world. To prevent Bill from invading the minds of his family, Ford devises a mystical barrier around the Mystery Shack that Bill will be unable to penetrate. However, nothing is stopping Bill from possessing anyone outside the Shack, and so he possesses the body of time-traveller Blendin Blandin. In the episode "Dipper and Mabel vs. The Future", Mabel becomes upset after Dipper tells her that he wants to stay in Gravity Falls and become Ford's apprentice. Having already been deeply disappointed by the lack of accepted invitations to her and Dipper's 13th birthday party, Mabel is deeply depressed and runs out of the Shack in tears, taking with her the dimensional rift still in its glass bubble. She runs into Blendin, unaware that he is possessed by Bill, who offers her the chance to alter time and make summer last forever so that she and Dipper will never have to grow up or drift apart. Blendin/Bill asks for the rift in exchange and the emotionally fragile Mabel agrees, handing it over. Blendin then smashes the rift globe to the floor, allowing the rift to open in the sky above Gravity Falls. Hordes of extra-dimensional monsters and bizarre anomalies emerge from the rift as Bill unleashes Weirdmageddon. After opening the rift, Bill gains physical form and imprisons Mabel in a bubble. He introduces himself to the people of Gravity Falls, claiming to be their new ruler as well as introducing his friends to the people. He begins remaking the town in his own twisted image, summoning a forbidding structure called the Fearamid which serves as his castle. Bill captures Ford, knowing that he might pose a threat, and turns him into a gold statue that he uses as a piece for his new throne which is made out of many petrified townsfolk. With the loss of so many people, the remaining citizens soon cease fighting back and struggle to survive in the chaotic hellscape that Bill has created. Blendin Blandin, however, returns to his own time and rallies the Time Paradox Avoidance Enforcement Squadron to put a stop to Bill's rampage. The Time Baby appears to confront Bill, but the triangular demon has become so powerful that he simply vaporizes Time Baby with a magical ray blast.

Dipper, with the help of Wendy and Soos, attempts to rescue Mabel from the magical bubble she has been sealed into. Bill sends Gideon and an army of creatures to stop them, but Dipper is finally able to convince Gideon that he will never win Mabel's love through selfish or evil acts, and so Gideon betrays Bill and helps Dipper and the others reach the bubble.

Whilst Dipper is inside the bubble trying to free Mabel from her perfect dreamscape, Bill punishes Gideon by forcing him to dance in a cage non-stop. Four days into his domination of Gravity Falls, he decides to take Weirdmageddon global, but a magical barrier prevents him from spreading his chaos beyond the town. He un-petrifies Ford to convince him to reveal how to destroy the barrier, but Ford refuses to be swayed by Bill's empty promises or his threats.

Dipper succeeds in freeing Mabel from her dream bubble and the twins reunite with Grunkle Stan and a handful of surviving townsfolk and magical creatures such as the Gnomes, the Multi-Bear and even the unicorn Celestabellebethabelle. The assembled posse decide to take the fight to Bill, and with the help of Old Man McGucket, they convert the Mystery Shack into a giant robot and use it to storm the Fearamid. While Bill and his hench-maniacs are distracted fighting the Shack-Bot, a rescue team consisting of Dipper, Mabel, Stan, Soos, Wendy, McGucket, and Pacifica Northwest sneak into the Fearamid. Bill fights the giant robot shack, but is prevented from attacking due to the unicorn hair barrier. Bill eventually discovers that the barrier doesn't extend to the robot's legs, so he exploits that weakness to destroy it. With aid from the captured Gideon, the rescue team save Bill's captive statues, including Ford. After a happy reunion with his niece and nephew, Ford explains that the way to thwart Bill is by using a zodiac with ten symbols. Each image represents a person, and once all ten people are gathered and holding hands, Bill can be defeated once and for all. For a moment, it seems that Dipper, Mabel, Soos, Wendy, Gideon, Old Man McGucket, Robbie Valentino, Pacifica, Ford, and Stan will be able to do it, but at the last moment, Ford and Stan break into an argument. Bill takes this opportunity to prevent the zodiac wheel from activating. He changes all but Mabel, Dipper, Stan, and Ford into tapestries, traps the men in a cage, and angrily chases Dipper and Mabel through the Fearamid after Mabel puts spray paint in his eye to distract him. After recapturing the twins he gives Ford an ultimatum--let Bill into his mind, or Mabel and Dipper will be killed. Ford reluctantly agrees, shakes the demon's hand, and lets Bill into his mind. However, Bill is shocked to realize that he, master of trickery and manipulation, has been deceived. He had not entered Ford's mind at all, but Stan's. While the demon was distracted chasing Dipper and Mabel, the brothers devised a plan to destroy Bill once and for all. They tricked Bill into going inside Stan's mind instead of Ford's by changing their clothes and impersonating each other and then Ford would shoot Stan with a Memory-erasing gun (from the episode "Society of the Blind Eye") which would completely wipe away Stan's mind and erase Bill from existence. Bill gets trapped inside Stan's mind and becomes terrified. He begs for his life and promises Stan anything he'd ever want, but nothing can sway Stanley Pines, not even losing his own identity in order to save his family. Once Stanford shoots his brother's mind away, Bill's form grossly distorts until Stanley punches him and Bill vanishes from existence while his physical body is turned to stone permanently. All his monsters, chaos, and damage done to the residents are sent back to where they came from.

Personality
Bill is an insane and physically irreverent demon who finds most things amusing (although no one is really sure why). He's outrageous and outlandish, as well as a quick talker and thinker. Though he may come across as simply annoying, he's not to be taken lightly; when angered, he's a force to be reckoned with as he will unleash his near-omnipotent powers on those unfortunate enough to make him angry.

Bill is not one who believes in rules. Instead, he follows his own selfish philosophy which means doing whatever he wants without care for the consequences. He thinks of laws and physics as senseless and displays an irresistible urge to break those rules down by causing absolute chaos however he can. The lives he ruins hold no merit to him and he finds amusement in tormenting and turning people's worlds upside-down. He also sees reality as an "illusion," and values its destruction.

When possessing Dipper's body, Bill is shown to be rather masochistic, hurting himself in various ways for the thrill of it, finding pain "hilarious." He seems to have little knowledge about the human body—specifically its physical limits. This comes back to harm him when he gains a physical form and endures pain when the shack mech rips out his eye, temporarily weakening him, or when Mabel spray-paints it shortly after.

Powers and abilities
Bill's abilities are focused around the mind and mental manipulation. He's described as a "dream demon" and displays some of the characteristics of a demon including creating contracts with his summoner. When he is summoned he appears to put everyone and anyone observing into a trance-like dream. The effect is that the world seems to turn colorless, and he can effect the surrounding environment however he likes, as demonstrated by pulling out and returning a deer's teeth. The people observing are unaware they've fallen asleep until Bill leaves and then they realize their eyes have been closed during his whole meeting.

Bill can enter people's minds through their dreams. Once inside a mind he can manipulate anything, including his shape and form and changing the landscape. He can communicate with his summoner like a video call, using his body as a window. In fact he can use his whole body as projector and display images. His body also seems to lead to a pocket space and runs in a slightly different time. (e.g., Mabel jumps into Bill's body and several seconds pass before she reappears, none the wiser.)

Once inside of a mind he can also easily pluck information from any others who are also inside and bring those ideas and images to life. The conjured images seem to take a life of their own.

Bill is also at least close to omniscient. He knows "lots of things," including the truth of many well known conspiracies as well as future events, such as the destruction of Gideon-bot and that Gideon Gleeful would go to prison.

Bill also has the ability to remove people's souls from their bodies, and take possession of the body afterwards. The person who is removed from their body is stuck in a ghost like form in the dreamscape, unable to affect the rest of the world, unless they find a vessel. This vessel doesn't have to be a living thing, as Dipper, who was a victim of this, used Mabel's sock puppets to warn her.

While Bill is certainly adept at the art of manipulation, even he has certain limits. While he can invade a person's dreams freely, he cannot force his way into a person's mind while they are conscious. In order to enter the mind of a conscious person, they must let him in of their own will, and so Bill frequently uses trickery and deceit in order to fool others into opening the door for him.

After the rift was opened, Bill gained a physical body and possessed almost god-like power within the mortal realm. He could project energy blasts, transmute matter, regenerate his body when injured and manipulate his own shape and size.