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Gideon Charles Gleeful, better known by his stage name, Li'l Gideon, is the main antagonist of the first season in the Disney channel animated series Gravity Falls, as well as the secondary antagonist-turned-supporting protagonist of season 2. He is a self-proclaimed television psychic. He owns the Tent of Telepathy and is a competitor of The Mistery Shack.
Season 1: June
Dipper and Mabel first learned about Gideon through his TV commercial and they wanted to test his authenticity as a psychic. They went to one of his shows even though Grunkle Stan forbade them from going due to Gideon causing him trouble. At the show, Gideon met Mabel and took a liking to her. He showed up at her house the next day and asked if she wanted to go to his dressing room so they could do makeovers which Mabel accepted. Gideon wanted to be more than friends with Mabel, but she didn't feel the same way, so she ended up breaking it off with him. Gideon believed it was because of Dipper, so he swore that he would get revenge on the entire Pines family. It later revealed that Li'l Gideon has the same book Dipper has, but his book is labeled 2. He also had an amulet that gave him his powers. In "Irrational Treasure", he dresses up as a tomato farmer on Pioneer Day and teases Stan by throwing tomatoes in his eyes after he insulted Gideon by saying he looks less girlier than usual.
In "Little Dipper", Gideon decides to take over the Mystery Shack. He fails twice, but discovers Dipper's Crystal flashlight which can grow and shrink things. He shrinks the twins and brings him back to his house. He calls Stan and uses the twins for ransom, but Stan doesn't believe him. Gideon heads over to the Shack, while Dipper and Mabel escape. Gideon catches them and shrinks Soos, believing he was Stan. He then corners Stan in his Maze of Mirrors. Dipper and Mabel tickle his armpit, immobilizing him and allowing the twins to take back the flashlight. Stan literally kicks him out of the Shack. Soon after, he is shown pacing around his house. His dad tells him he'll get his revenge one day, but Gideon angrily tells him it's not just about revenge; he wants the Shack so he can find a hidden secret.
in Dreamscapers, he summoned a dream demon named Bill Cipher to get him the code for the deed for the Mystery Shack. This plan fails and he switches to plan b: dynamite. The episode ends with a cliffhanger.
In the season 1 finale Gideon Rises, Gideon steals the shack and tried to replace it for Gideonland and find the third and first journal so he can tule gravity falls however at the end stan reveald that Gideon is a fraud. Angered, Sheriff Blubs and Deputy Durland decide to arrest Gideon. But before they did Stan took journal 2 from him and the deed for the shack. The Pines family turned out as the heroes of Gravity Falls. Near the end of the episode, Soos is reading the newspaper and a picture of Gideon in his cell is seen at the back.
He apears in a leaked short where he is seen in jail with a new gang with him as there leader.
As of the Weridmageddon arc, Gideon redeems himself after Dipper convinces him if his actions are going to make Mabel happy.
Li'l Gideon is a stout kid who acts much older than he seems. His appearance best resembles a pig. During most of the series he wears a baby blue suit, black shirt, an American flag pin, brown fancy shoes, and a green amulet. When he touches this amulet it glows and gives him special powers. It is later discovered that this amulet is featured in the Book 2. Until Mabel destroys it in "The Hand That Rocks the Mabel," he wears a jade amulet on a bolo tie. In Irrational Treasure, it is replaced by a white tie.
Mabel Pines Shortly after his first encounter with Mabel, Gideon fell head over heels for her, and continually attempts to get Mabel to return the feeling through various schemes, but to no avail. Despite his crush, Gideon seeks revenge on Mabel and her family (whom he views as the only thing standing between a successful relationship). Mabel, on the other hand, finds Gideon to be creepy and unattractive, not to mention totally evil, and despises him and every attempt he makes to enact his vengeance.
Gideon and Dipper are mortal enemies, and are frequently in combat. Gideon sees Dipper and the rest of his family as a threat to be dealt with, so as to get revenge, win Mabel's love, and seize control of the Mystery Shack and its secrets. Thus, he spends his free time plotting and executing complex schemes, none of which succeed. At the same time, Dipper dislikes Gideon just as much and is the frequent victim and stopper of his young enemy's evil plans.
For unknown reasons, a rival has existed between Stan and Gideon for years. Business rivals to begin with, their rather competitive personalities fuel their feud further. Gideon wishes to eliminate Stan for numerous reasons, namely to take control of his business and a strange secret it possesses and to remove the "obstacle" to winning Mabel's affection, and he plots day and night to figure out a means of revenge, though he is sometimes satisfied with simply irritating Stan. Stan doubts Gideon's abilities and constantly teases him.
Though a father traditionally has authority of his son, Gideon's and Bud's situation seems to be the complete opposite: Gideon bosses Bud around and Bud submits without a second thought. While Gideon just utilizes his father as a tool to help him reach his goals, Bud nonetheless loves his son and is willing to do much for him, seeing the boy as "precious."
Due to her son's sinister and intimidating nature, Mrs. Gleeful is submissive to Gideon and fears him, trembling at the mere sight of the young boy. Gideon lacks respect for her and treats her abusively.
Li'l Gideon is a self-proclaimed television psychic whose real mission is to take down his competition, The Mystery Shack. He uses his "cuteness" to get what he wants and he admits that people have a hard time saying "no" to him because of it. It seems that he can be kind and charming when he needs to be, as seen with most of his times with Mabel. He speaks with a Southern American dialect. He is spoiled, ungrateful, selfish, and abusive toward his mother and father, such as throwing ice cream, yelling at them, and breaking lamps. His mother appears to fear him. He can also appear very rude and obnoxious, an example is shown in "Little Dipper", where people are buying cars from his dad and talks behind their backs, and when he shrinks Mabel and Dipper.
Gideon's greatest talents are charm, deceit and scheming. In The Hand That Rocks The Mabel, he begins dating Mabel, against her will, after seeing her in the audience of one of his performances. Unabe to end the relationship, Mabel sends Dipper to tell Gideon "It's over," but Gideon takes it badly, screaming that Dipper had "turned her against him." He attempts to kill Dipper using his amulet, but is stopped by Mabel, who destroyes the amulet, thus elminating Gideon's powers.
Later, in Little Dipper, he formulates many plans to exact vengeance on the Pines family, ultimately leading to shrinking them to take possession of the Mystery Shack. He also possesses 2, a prequel to Dipper's 3 that appears to contain mainly alchemical secrets, and therefore knows of and has access to many supernatural items, such as a Mystic Amulet that gave him telekinesis (destroyed by Mabel) and cursed Egyptian super termites.
- He is voiced by Thurop Van Orman, who also voiced Flapjack in the series The Marvelous Misadventures of Flapjack.
- Li'l Gideon is first seen on the back of the Wacky News magazine that Dipper had in "The Legend of the Gobblewonker," though he didn't physically appear until "The Hand That Rocks the Mabel".
- Li'l Gideon's appearance is based on Benny Hinn, a famous Christian televangelist who claims to be a prophet.
- A picture of Gideon appears on a board in the Gravity Falls theme song, "Made Me Realize."
- A variation of bill cipher can be seen on a paintbrush jar in Li'l Gideon's room at the end of the episode "The Hand That Rocks the Mabel."
- He has a hamster named Cheekums.
- Gideon's school ID number is 618 which is also The Mystery Shack's address and Alex Hirsch's birthday.
- He resembles Chowder from the Cartoon Network series of the same name.
- His villain songs are Little Ol Me and Lil Gideon (song)