Bill Cipher

Stanford Pines is a paranormal investigator. Born with six fingers on each hand, Stanford spent years studying the anomalies of a town called Gravity Falls, Oregon, before becoming trapped in an interdimensional portal created with Bill's help. Stanford was the key piece, the intellectually superior genius and the necessary bridge to bring Weirdmageddon into the third dimension. Bill manipulated Stanford's loneliness and ambition, presenting himself as a muse to get him to build the Universal Portal.

Stanford meets Bill Cipher, who deceives him by pretending to be his friend and fabricating the truth in order to create a portal that leads to the malevolent triangle, to the protagonists' dimension. Finally, he discovers the truth and shuts down the portal he created with Fiddleford, a former college friend.

Upon deciding to investigate the supernatural occurrences in Gravity Falls, he stores the information in three different journals, which he asks Stanley to hide. However, after having a fight with him, Stanley accidentally pushes him, causing him to trip and fall into the portal they activated during the fight, and be sent to another dimension: The Nightmare Kingdom.

Once he was on the other side of the portal, he pulled out a second pair of broken glasses that he always carried with him. Bill sent all his allies after learning of his presence, so he had to hide in the shelter of some travelers who possessed a device that allowed them to transport themselves between dimensions. It was then that he left Bill's dimension to steal materials to make a weapon powerful enough to destroy him.

Ford traveled to a parallel dimension. There, he encountered what his future would have been had Bill not ruined it by creating his portal. In that place, a way had been found to avoid even the slightest risk of connection with the Nightmare Realm, and his cabin had become the International Institute of Weirdness. He was drawn to the Institute like, in his words, a moth to a flame, and before finding his own counterpart, he encountered the Fiddleford equivalent, who isolated him for everyone's safety. The parallel Fiddleford gave him a material that allowed him to complete his weapon, so he decided to return to the Nightmare Realm to finish what he started.

Allies:
8-ball
Kryptos
Xanthar
Hectorgon
Pyronica
Teeth
Lock
Pacifier
Amorphous Form
Demon Lava Lamp
Gideon Alegría (Formerly)
White Eyes (Formerly)

Enemies:
Dipper Pines
Mabel Pines
Stanley Pines
Stanford Pines

Bill Cipher has multiple appearances but is always a one-eyed, yellow, 2D triangular being with a black top hat and a triangular bow tie; his arms and legs are also black. He is not humanoid; he is literally a triangle with arms and legs.
Bill has the ability to change his appearance, both in color and physical form. When he displays anger, his yellow body changes to a bright red. Bill can change his physical shape, but he will always be a triangle. For example, he can be larger or smaller because he is a demonic being and not a mere mortal. Bill does not possess a mouth, but he can appear to have one with his single eye, as it can be seen that Bill eats with his eye, specifically with his eyelids.

Bill possesses incredibly powerful abilities, such as entering and manipulating the minds of living beings. Beyond minds, Bill can manipulate reality, time (due to his destruction of the Time Baby), and matter at will. For example, he pulls out the deer's teeth in "Dream Escape," fires destructive beams, stops or travels through time, alters the holes in Preston Northwest's face in "Weirdom: Part 1," transforms people into banners, stone, wood, or gold (as he did with Stanford Pines in Weirddom 3: Take Back the Village), and can shapeshift. His destructive beams are so powerful they could kill the Time Baby and its guards. He can possess people and/or objects and can fly, which is why he doesn't use his feet much. He can play the piano and possesses overwhelming strength, enough to kill a person by tearing them apart molecule by molecule with his bare hands.

He is very good at deceiving people into fulfilling his purposes, which throughout the series are mainly to find a new place to live, since the Nightmare Kingdom, his home, was going to be destroyed.

Bill can also possess people's bodies if they make a deal with him. When this happens, the possessed person will have yellow sclera and vertical pupils.

Bill also seems to have the ability to predict the future, make nefarious deals for his own benefit, although he does keep his promises, etc.

Bill is based on the Eye of Providence, possessing an "exoskeleton" (covering him from the outside) that resembles a fluorescent yellow triangle. He has a large, feline-like eye with eyelashes, and brick-like features on the lower part of his head. He moves by floating and rarely uses his feet. He has black legs and hands, a black top hat, and a bow tie. He also carries a cane (which he almost never uses). He appears in the episode "Dream Escape." At times, he seems to radiate a yellow glow.

His physical form can change over time, as he once had a baby form. In his baby form, he had very short, yellow arms, a very large eye with only three eyelashes above it, and he was seen wearing large blue shoes with Velcro straps. This suggests the possibility that his arms turned black as he grew up, or that Bill currently wears gloves. In the same book, Bill currently has a crack near his eye after being punched by Stanley Pines.

Bill is a dream demon who finds everything amusing and feels no remorse when killing or destroying things. He's a manic, unpredictable, and even sadistic character. An example of this is the episode "Love Without Socks," which features macabre and bizarre behavior. He also stated that, for him, pain is "funny." He usually appears carefree when he first appears, but when angered, his demeanor changes rapidly. He only thinks about himself and his goals, and he seeks to harm those responsible for his anger.

Bill's goal is to get someone to break the Dimensional Rift so his friends can reach Earth and Weirdmageddon can take place.

Bill's personality is also egocentric and egotistical, and he is rarely intimidated by those who threaten him. When he realized he was going to be "eliminated," he felt true despair, going so far as to beg Stanley that he could give him anything he needed to avoid being eliminated, including fame, money, and infinite knowledge.

Bill is a manipulative being who, despite initially appearing helpful, ends up manipulating people for his own benefit so that he can use them to achieve his goals.

Bill is traumatized by being the sole survivor of his childhood home and the sole survivor of his family.