She was first mentioned in "Henchman", while Finn and Marceline were in the strawberry fields, where the latter mused that when the sun burns her, it reminds her of when she would scrape her knees as a child and her mom would patch her up.
Elise makes her first physical appearance in "Everything Stays" in one of Marceline's flashbacks, where she is shown living with her daughter in a trailer somewhere in the desert. She is briefly seen telling Marceline about how she met Hunson. When Marceline says that she does not want to take a nap because her dreams are weird, Marceline's mother comforts her by telling her that her dreams might just be normal things viewed from a different angle and singing her a lullaby, "Everything Stays."
During "Obsidian," through flashbacks it is discovered that after the Mushroom War, Elise and Marceline were trying to reach a fallout shelter called the Clubhouse. Throughout their journey, Elise becomes more and more sick and eventually starts coughing blood. Knowing that she won't make it, she sends Marceline ahead telling her she will fix a motorcycle to get there. Marceline interpreted this as Elise abandoning her after witnessing her demon powers, but later found an audio recording where Elise apologized, explaining she didn't want Marceline to watch her mother die.
Marceline's father makes a brief, mournful reference to Marceline's mother in The Adventure Time Encyclopædia: "Thus, regarding her childhood adventures with her poor, unfortunate mother, there is, now and evermore, naught to be heard but the Shadowfall of Nightospheric Silence."
Marceline's mother is heavily mentioned in Adventure Time: The Enchiridion & Marcy's Super Secret Scrapbook. Being so young, Marceline only had a few scarce memories of her mother, who mysteriously vanished by the time Simon Petrikov found her. All that she left behind were two photos of her and Marceline together and a letter placed in Marceline's pocket mentioning Hunson and to keep Marceline safe. Before hibernating, Marceline looked up the last two pictures of her mother to cherish their memories together and hoping that she would dream about her.
More information about her death is seen in the episode "Obsidian." It is revealed she and Marcy survived the Mushroom War, but Elise came down with a deadly illness that was causing her to cough up blood, implied to be radiation poisoning from the nuclear fallout. As it turns out, Marceline's impression of her as having abandoned her stemmed from an incident where Elise watched Marceline kill a wolf that attacked them: Marceline believed Elise feared her and ran away, not realizing just how sick Elise was and that she wanted to save Marceline from having to watch her mother die.
- "Obsidian" (flashback)
- "Henchman" (mentioned)
- "Everything Stays" (flashback; official debut)
- "The Dark Cloud" (flashback)
- "Ketchup" (pictured; imagined as Moon Lady)
- She was first confirmed to be a human at Wondercon 2013.
- Her original voice actress, Rebecca Sugar, formerly worked on Adventure Time as a writer and storyboard artist before creating her own show, Steven Universe, which also aired on Cartoon Network.
- Her name was first revealed in the ending credits of "Obsidian."