Sunset Shimmer

Sunset Shimmer is a female unicorn and the main antagonist in My Little Pony Equestria Girls. Her Playful Ponies toy box says "Sunset Shimmer knows a magical path to faraway adventures! Years ago, she was also a student of Princess Celestia."

Development
Sunset Shimmer resembles the G3 Earth pony Sunshimmer in pony design and name.

An image posted online in mid-March 2013 depicts human Sunset Shimmer with pony ears and longer hair, similarly to the six main characters of Equestria Girls in part of the film and in some other material.

On March 19, 2013, Meghan McCarthy was asked "Is Sunset Shimmer going to be a Season 4 storyline? The fact that her backstory seems like a show plot" and responded "Nope." On April 1, 2013, McCarthy wrote as part of an April Fools' Day joke that My Little Pony Friendship is Magic season four episode five would be titled "The Student Becomes the Teacher: The Return of Sunset Shimmer".

Depiction in the film
Sunset Shimmer appears in the film My Little Pony Equestria Girls as the main antagonist. She is a pony who steals Twilight Sparkle's element of magic crown, and in a tussle with Twilight, the crown is thrown into a mirror that acts as a portal to another world, which Sunset goes through to get the crown. In this other world, she is depicted as a human who acts very disrespectful and mean to Twilight when they first encounter each other. Later, she puts on the crown and transforms into a demonic-looking winged humanoid. Once she is defeated by the main characters, she returns to her human form. Afterward, a human woman resembling Princess Luna hands her a masonry trowel.

My Little Pony (mobile game)
Sunset Shimmer is to be added to Gameloft's mobile game. In the first week of June 2013, Hasbro's My Little Pony Facebook page and the official Facebook page of the game posted the clues "The path to a new adventure is magical...", "Everyone will love me now!", "Beware, Equestria!", "A beautiful pony that has nothing but power and potential", "I'm better than all of you!", and "Magical mirrors shimmer".

Merchandise
A Playful Ponies toy of Sunset Shimmer was displayed wearing a masquerade mask at the 2013 New York Toy Fair, and was released with the mask and a comb as part of the Crystal Princess Celebration line. The back of the release's packaging bears the general statement "The ponies wear beautiful masks to dress up for a special celebration!" and the specific statement "Sunset Shimmer knows a magical path to faraway adventures! Years ago, she was also a student of Princess Celestia."

Quotes
"You must be new here."

- Both trailers

"Where is this Twilight Sparkle?"

- First trailer