Marshall Lee

Marshall Lee (full name: Marshall Lee the Vampire King), is the gender-swapped version of Marceline, created by the original series designer, Natasha Allegri which is featured in "Fionna and Cake.

Abilities
Marshall Lee supposedly has the same abilities as Marceline, since he was first seen floating.

Appearance
Marshall Lee has a slim body, has an average height, pointy ears and light blue skin.

He has a matching permanent bite mark like Marceline. He initially wore a grey plaid shirt, but now wears a red and grey plaid shirt. He also wears dark blue jeans, and brownish-red with white sneakers.

Personality
Personality-wise, Marshall Lee should be similar to Marceline. He appears to have an interest in music like Marceline, as he's shown to own a guitar and he gave Fionna the devil horns, a popular hand sign amongst heavy metal and rock n' roll fans.

Trivia

 * Marshall Lee and Marceline both have regular electric bass guitars, as seen in the openings.
 * Rebecca Sugar said that she fought for Marshall Lee to have a few lines (such as "Whoa, Fionna! You're wearing a dress? That is cra-azy, son!"), but they were cut for time. She wanted him to be voiced by Dante Basco.
 * In an interview with Pendleton Ward at Comic-Con, he stated that the next genderbent episode would mostly focus on Marshall Lee.
 * Pendleton Ward officially addressed Marshall Lee as "Marshall Lee the Vampire King."
 * An alternate character sheet depicts him with green skin, but it was only used in one scene with a special lighting.