Finn's mom

 is a character that first appeared in "The Lich." She exists within a dimension called Farmworld, where Finn and Jake were sent to after they get pulled into a portal to another universe chasing after the Lich. She appears after Finn and Jake are dragged through the Lich's portal, where she calls to Farmworld Finn (who has a different face and a robotic arm) to come inside, and that it's very important he do so. She lives in a house similar to the farm house seen in the episode "Thank You."

Appearance
She wears a pink dress and what appears to be a wedding ring on her finger.

Animatic clip
An animatic clip that was posted on the Adventure Time blog showed Finn's mother asking him to sell their mule Bartram for "as much as you can." She seemed to worried, as Finn's father is being pushed around by "the Destiny Gang" just outside the house, in the fields. When Finn sees this, his mother soothes him "Finn, please, everything will be fine, I promise. Just do as I say." She is also cradling a baby in her arms.