Elsa

The Snow Queen, also known as Elsa , is a character on ABC's Once Upon a Time. She débuts, with her only appearance, in the twenty-second episode of the third season.

She is based on the Snow Queen from the fairytale, The Snow Queen.

History
While trapped in the past, Hook, Emma and Marian are sealed in Rumplestiltskin's vault. The room is full of dark magic artifacts too dangerous for Rumplestiltskin to use. A vessel in a cabinet catches Hook's eye, and he casually pulls it out. When Emma regains her magic and re-opens the time portal to return to the present, the vessel is also pulled through. Once the trio depart, the vessel opens and releases a blue liquid that changes into the form of the Snow Queen, Elsa. She destroys the vessel and walks out to explore Storybrooke while creating a walkway of frost.
 * -|During New Curse=