This isn't over. This isn't the last you'll see of li'l ol' me.
Gideon Charles Gleeful is a former child television psychic, once the hero of Gravity Falls and the owner and operator of the Tent of Telepathy, an unsuccessful suitor for the love of Mabel Pines, and the sworn enemy of her Grunkle Stan and her brother Dipper. Like Dipper, he owned one volume of Stanford Pines' three volume Journals -- not, however, as an inquirer into mysteries but as a seeker after absolute power. When defeated by Dipper and Mabel and exposed as a fraudulent psychic by Stan, he vowed revenge against the Pines family.
At the time of the Fusion Invasion Mabel was launched by an otherwise harmless beam of light all the way to Murky Woods; it was unclear at first who was behind this, but it was later revealed to be Li'l Gideon. In the mission "Li'l Destruction," in order to prevent Gideon from sending his creepy love letters to her, Mabel asks the player to go to Volcano Mountain and destroy the diary which he uses for material. Mabel asks the player to read it first, and as the player does, it is revealed that it is actually one volume of Ford's journals, and that Gideon used one of its spells to create the mysterious beam of light. Before the journal can be recovered, however, Fusion Dipper steals it. The player follows the Fusion to its Fusion Lair, and must fight many Flame Zombies before reaching the Fusion duo. Even if the player manages to beat him, Fusion Dipper nevertheless escapes with the journal. Gideon is in the Lair, and informs the player that the journal held many of the secrets of Gravity Falls — dangerous ones. He tells the player that Fuse now has a greater advantage. The player must then relocate Fusion Dipper, who has now been joined by Fusion Gideon, and defeat them both, before he returns the journal to Dipper, who is unaware that Gideon even had his book.
Gideon is said to be based on televangelist Benny Hinn, though he also seems to resemble disgraced televangelists Jimmy Swaggart and Jim Bakker.
Though, like most other child characters in FusionFall, Gideon has been aged up to a teenager, he retains his dwarfish stature and has merely become stouter and grosser.