|Friends:||Finn and Jake|
|Occupation:||Idol of Finn and Jake-Hero|
|First Appearance:||His Hero|
Billy is a character who appears in "His Hero." Billy is Finn and Jake's idol and the most powerful hero seen in the series. Thus, the two are immense fans of him.
As described in "Billy's Song," when Billy was younger he was a hero of action much like Finn. He is known to have rescued Cotton Candy Princess from Fire Count, slain an evil ocean, and fought against a giant bear. Perhaps most importantly, he's also said to have defeated the Lich.
When Finn and Jake finally meet him, he is old (his red hair turned white) and he frowns upon violent heroism like theirs. He hated the futility of fighting evil when more would always pop up later, so he chose to help people indirectly through non-violence. He even had his own magical dog, though it is deceased by Finn's time. Finn and Jake try to follow his example of pacifism but end up returning to their violent ways, with Billy's eventual admiration.
Billy is very tall and has a long beard and long hair which looks like that of a caveman. Each of his unusually large hands has six digits: 5 fingers and 1 thumb. Most Humanoid in Ooo possess four-fingered hands. He has blue veins bulging out on the back of each hand. Billy wears no shirt or shoes, and has brown pants.
He bears a strange scar that looks like he had stitches on his left shoulder. During his younger days he possessed a gauntlet with a jewel on the wrist and an eye on the top of the hand which he used for combat, including and most importantly during his battle with The Lich. He has a void in his chest where his heart would be until Finn's bold words fill it in "His Hero." He also appears to have a magic sword called "Nothung," which he can summon by calling its name. He is almost as big as The Lich.