The Skeleton Army is Marceline's army of the undead, which she raises from a graveyard in "Henchman." The army consists of twelve undead skeletons with assorted weapons and shields. To summon them, Marceline chants, "Corpses buried in mud that's black, from death I command you to come back!" Although Finn thinks they are going to attack the Duke of Nuts' castle, they really just go there to celebrate the Duke of Nuts' second son's first birthday. They also appear in "Bad Little Boy" when Marshall Lee summons them to fight Fionna.