Fallen Hero is an Adventure Time fanfic by Futanari Is Fail, better known on This Very Wiki as SizzlyBacon. The story is told all from Finn's perspective, but due to tragic events, he has forgotten his own name, and is retelling his account of the death of Princess Bubblegum and Marceline (who... by the way... were kind of in a committed relationship.), the man who killed them (who, apparently, is supposed to be Finn's brother, or an alien, or any combination of the two), Finn's relationship with the man, and how he learns to deal with the recent change of events. Wait, what?