Death

Death is the ruler of the Land of the Dead in the episode "Death in Bloom". He plays the drums in a competition against Finn. He almost kills Finn, but then Finn brings up Peppermint Butler and Death gives back Jake's memory and the life of Princess Bubblegum's plant. He is shown to have various powers, such as the "Kiss of Death", encasing people in forcefields, and sending people back to the Land of Ooo.

Trivia

 * In certain religious views, Death is referred to as the Grim Reaper, or the Angel of Death. He is the one who causes the death of victims and sends them to the afterlife. His traditional appearance is a skeletal figure carrying a large scythe, and is clothed in a black cloak with a hood. The very touch of death will instantly cause his victims to die.
 * Death was originally going to be some sort of Japanese cosmic alien, according to Jesse Moynihan's blog. He later tried a design inspired by Alejandro Jodorowsky's The Holy Mountain before changing the head into a horse skull.
 * When Death said, "I'll see you guys later" to Finn and Jake, he probably meant when they die and are sent to the Land of the Dead.
 * Death's appearance as a farmer is likely a sublime reference to his trademark item, a scythe, which is a piece of farming equipment.
 * During the musical battle, he growls and mumbles in a way that possibly references or parodies 'death metal' bands.
 * Whenever someone drinks the water in the Land of the Dead, he can kiss them so that the person can regain his or her memory.
 * Although Death is one of the most powerful beings in this universe, there are some characters who can "cheat Death" and thus not be able to be controlled by him, such as The Lich and Marceline`s dad.
 * Death is a known friend of Peppermint Butler, suggesting that Pepperment is a demon (in addition to him wanting to eat Finn and Jake's flesh in Death in Bloom... and then threatening to take it in their sleep, and him hissing at a possessed Princess Bubblegum in Mortal Recoil).
 * The fact that Finn must have a musical battle with Death to get Jake's memory back might be a reference to the song "The Devil Went Down To Georgia" as The Devil challenges a boy named Johnny to take his soul. Only Finn fails miserably in contrast to the song.
 * He bares a striking resemblance to white spy from "Spy Vs Spy".

Quotes
See Death/Quotes