Princess Ember, also called Dragon Lord Ember and Ember, is a female dragon princess and ally/friend of Spike. She first appeared in the My Little Pony: Friendship is Magic season six episode, Gauntlet of Fire.
Princess Ember appears with her father in the season six episode, "Gauntlet of Fire" When the dragons of Equestria are gathered together by Torch to compete for the title of new Dragon Lord, Ember tells her dad she wants to participate, but is forbidden because of her small size.
Against Torch's wishes, she disguises herself in armor and green body paint to secretly part in the Gauntlet of Fire. She almost drowns in the first leg of the race, but Spike saves her. Ember discovers Twilight and Rarity and when Spike says they are his friends, Ember says "dragons don't do friends". However, when Garble almost discovers Spike's friends too, Ember covers for them and Spike hides her identity when Garble almost recognizes her. She agrees to partner up with Spike after he suggests working together in order to face the Gauntlet's more daunting obstacles.
Ember and Spike make it through several obstacles together and make it ahead of most other dragons competing, including Garble. However, Ember eventually tells Spike that since there can be only one winner it is "every dragon for themselves" and ditches him, saying that they aren't friends. Ember returns shortly afterwards, in time to save Spike when Garble tries to kill him during the competition, and apologizes to him for abandoning him. The two face Garble together, with Ember holding him off while telling Spike to grab the scepter. Spike eventually gets the scepter and wins the contest, with Garble and all other dragons standing down, but he relinquishes the scepter and title to Ember, knowing that she will be a good leader to the dragons and will keep the ponies of Equestria safe.
Ember appears in a simulation produced by Twilight when she considers the Dragon Lands as a possible place to send Starlight Glimmer.
Spike accidentally invites both Ember and Thorax to Ponyville on the same day. During her visit, Spike acts distant as he tries to keep her and Thorax apart, causing her to feel ignored. When she eventually confronts Spike about this, she gets into a brief conflict with Thorax, mistaking him for a bear that wishes to cause Spike harm. After the misunderstanding is cleared up, Ember helps Thorax to be more assertive toward his subjects, and he helps her to express her feelings in a calm manner. After she and Thorax reconcile with Spike, they both take part in a ceremony to unite dragons and changelings in friendship.
To Change a Changelling
Ember is mentioned by Starlight when she tells Thorax about her teaching him to be assertive.
Shadow Play, Part 1
Ember is mentioned by the dragons in the Dragon Lands, with it being revealed she has commanded her subjects to make peace with the ponies.
School Daze, Part 1
Ember appears in School Daze - Part 1 at the School of Friendship representing the dragon student Smolder. She also attends the "Friends and Family Day" gathering which is inadvertently ruined by Smolder and her fellow students. After Chancellor Neighsay insults Ember and the other leaders, she angrily decides to take Smolder out of the school.
School Daze, Part 2
When the students are found after they run away, the Mane Six convince Ember to let Smolder re-enroll at the school, against Neighsay's authority and wishes.
Ember makes a non-speaking cameo, signing Smolder's permission slip to return to Equestria early and honor the Tree of Harmony after Smolder proves herself by beating another dragon in arm-wrestling.
Sweet and Smokey
Ember watches over the dragon eggs during "Baby Dragon Hatching Season" and meets Fluttershy when she comes to see the eggs hatch. Ember notes the eggs are overdue and isn't sure why they aren't hatching. Spike meets up with her and they discover that the hatching grounds have gone cold, because Garble's friends have redirected the lava from underneath the hatching grounds and have unknowingly been freezing the eggs.
Ember orders all dragons to the hatching grounds to provide heat for the eggs themselves. After Garble saves the eggs by getting the dragons to laugh at his beat poetry and the resulting "laughing fire" being hot enough to heat and hatch the eggs, Ember calls him "The Hero of the Dragon Lands".
Between Dark and Dawn
Ember makes a cameo appearance during the song "Lotta Little Things".
The Ending of the End Part 2
Ember is present when Smolder gives a speech to the Dragon Lands about helping other creatures and being kind and generous and appears during the final battle against the Legion of Doom as part of the army arriving to help the Mane 6 and Spike.
The Last Problem
Ember attends Twilight's coronation ceremony in the flashback and appears in one of the group shots during "The Magic Of Friendship Grows".
Wings Over Yakyakistan
Ember appears in the My Little Pony: Friendship is Magic Issue #55-56 story arc Wings Over Yakyakistan, in which Yakyakistan comes under threat from dragons. She appears leading the dragons' charge. Ember accuses the yaks of breaking a sacred bond between the dragons and yaks. With Spike's help, the two groups come to a peaceful solution, and Ember vows to be make herself more worthy of the title of Dragon Lord.
Convocation of the Creatures!
Ember attends the Convocation of Creatures as representative of the Dragon Lands, where she meet and tells Twilight that she not use to be a diplomacy. Princess Twilight convinced her for doing her great job for resenting the dragons before Ember going to the buffet table for some sulfur seltzer.