|Hair||Red and Yellow|
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 back story 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"
Sunset Shimmer appears in the film My Little Pony Equestria Girls as the main antagonist. She is a Unicorn 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 and apologizes for her actions. Afterward, Vice-Principal Luna hands her a masonry trowel.
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."
PersonalitySunset Shimmer is the polar opposite of Twilight; cruel, dishonest, arrogant, mean-spirited, cold-hearted, tyrannous, evil, selfish, power-hungry, and a bully.
She uses her severe nature to intimidate others, which causes her to become Princess of the Fall Formal. She has a tendency to cruelly demoralize those who get in her way, such as when she posted humiliating videos of her online and framing Twilight for vandalizing the decorations to Princess of the Fall Formal.
When she puts on the crown and becomes a demon, she becomes far more sadistic and malevolent, as she hypnotizes the students and student body to become her slaves and almost kills Twilight. When she reverts back to normal, Sunset Shimmer had a total change of heart, as she has became regretful of her actions, and horrified of what she had become. Twilight asks her friends to become friends with Sunset Shimmer, as she never had a friend before. She also accepted her punishment near the end of the film to repair the school from all of the damage she made.
In Rainbow Rocks, Sunset Shimmer is heavily ostricised by her schoolmates for what she did at the Fall Formal. However shea has also become humble and loyal. In the kitchen scene, she provides support for Twilight when she is feeling discouraged.
"Sorry it had to be this way... princess!!"
"You must be new here."
"Where is this Twilight Sparkle?"
"Can't believe I didn't recognize you earlier. Shoulda known Princess Celestia would send her prized pupil here after my crown, and her little dog, too."
"Take those off! I have something I need you to do."
"I wouldn't dream of it. I'm no monster Twilight."
"Equestria! Your friends! Lost to you forever! Don't you see what I'm about to do to the portal?"
"Yes, she's so very special!"
"I'LL take that!"
"At last... More power than I could ever imagine."
"But let's let by-gones be by-gones. I am your princess now, and you will be loyal to me!"
"Gee, the gang really are all back together!"
"She has to be done with!"
"I'm sorry. I'm so sorry. I didn't know there was another way."
"But. All I've ever done since being here is drive everyone apart. I didn't know the first thing about friendship."
- Sunset Shimmer's human form bears some resemblance to the female gang members, The Jezebels in the infamous gang film, Switchblade Sisters.