Bill is a legendary demon who is more powerful than any other nightmare creature and older than the galaxy. The Second Dimension, where bill cipher formerly resided, was a “flat planet with flat minds and flat thoughts” that he promptly obliterated. Once Bill had made up his mind to cause chaos and ruin, he was compelled to “liberate” his dimension by eradicating everyone and everything inside of it—including his parents. He eventually made it to the Nightmare Realm, where Bill quickly encountered the Henchmaniacs. As Bill had no physical form in this dimension, he could only access or control human minds. Bill used this power to control innumerable people to find a way into the Third Dimension, take on a physical form, and free it as well.
Bill’s encounters were documented across human history for trillions of years. He once came across locals who were residing in the area that would one day become Gravity Falls, Oregon. The people decided Bill was too dangerous and devised a zodiac with 10 distinct symbols to combat him. They also left behind an artwork of their experience with the monster, summoning instructions, and a note never to read it.
When Stanford Pines arrived to examine the town in the late 20th century to learn more about Gravity Falls’ peculiarities, he came across this symbol. Ford eventually ran into bill cipher in his dreams after failing to call the entity, where he offered to help with the universe’s mysteries and win Ford over. Ford accepted the arrangement because he was duped by the charm.
Then, Bill, had Ford construct a device he said would help humanity but which was a portal enabling the demon to access the third dimension. Fiddleford McGucket, one of Ford’s human companions, realised the portal’s actual purpose and forewarned him before they finished their work. Ford was horrified and felt deceived, so he halted the research, hid all three operating manuals, and started developing defences in case the demon ever made a comeback. Bill, on the other hand, waited patiently for the portal to restart.
Bill frequently appears in Gravity Falls before making his film debut in “Dreamscaperers.” In the online game Rumble’s Revenge, he was an anonymous character that created the cryptograms. By adding up the capital letters of Rumble’s Revenge’s cryptograms, which result in the phrase “MY Identity IS BILL,” one can determine both his name and existence.
Bill’s image momentarily appears after the opening tune. This picture is a portion of the one from his entry in book 2. Numerous symbols that can be connected to different show characters are all around him. Most notably, he refers to Dipper, Mabel, and Soos as “pine tree, shooting star, and question mark,” respectively, when he first manifests physically.
Bill wears a top hat, and a bow tie, and sticks his arms and legs in the theme song, but not in most of his cameo appearances. As a metaphysical monster, Bill has the power to transform his body into several terrifying cubic shapes. Despite being able to control his own body at whim, Bill’s wounds seem to indicate that his interior has an organic, flesh-like texture.