Door Lord

Door Lord is a character who first appears in "What Was Missing." Door Lords (or at least this one) help people learn that friendship is the most valuable possession you can have by stealing other peoples' prized items. Princess Bubblegum and Marceline once had them locked away (Marceline wanted to kill them rather than imprisoning them) but they escaped since they were able to open door-like portals.

Abilities
The Door Lord has the power to throw keys and teleport by making doors appear that lead to a myriad of places. They can also jump very high, which Jake acknowledges by saying "That guy must do crazy squats!"

Appearance
The Door Lord looks very similar to Key-per, having the same skin color and big cheeks, but is much taller and has more muscle mass. They have multi-angled appendages, allowing them to turn in abnormal ways. Door Lords also wear doors on their heads, similar to the way Key-per wears a key on his head. He wears no clothes except a bright blue backpack with keys hanging on the bottom.

Trivia

 * The Door Lords appear to be a similarly themed species to the Key-per, but are very different in many ways.
 * Key-pers have the power of opening Doors with their big keys, the Door Lord possess the ability to create doors to anywhere.
 * Key-per are small in appearance, whereas Door Lords are giants who tower over the rest of the cast easily.
 * While Key-pers are known to be very fast talkers, the Door Lords have taken vows of silence and only mumble.