Marshmallow is an episodic minor antagonist in season 4 of Once Upon a Time, appearing in the episode A Tale of Two Sisters. A fierce snow monster who is summoned by Elsa. He is from a 2013 Animated Disney film Frozen.
When Elsa was pursued by Emma Swan and Killian, she summons Marshmallow for her protection. Marshmallow scares the duo away, and weak havoc across town before entering the forest. He crosses paths with the Merry Men, and is angered into attacking them after they shoot him with an arrow. Before he can crush Maid Marian, Regina Mills intervenes by destroying Marshmallow, leaving behind the snow that had formed him.
- Unlike his Animated Disney Version, he is considered a villain instead of being considered an anti-villain/anti-hero, but later destroyed.