1: Derpy and Carrot Top are exploring an ancient ruin they've stumbled across on their way home. Skeleton ponies are moving to try and keep them out.
2: Derpy and Carrot flee deeper into the ruins to escape the skeleton ponies, when a mysterious earthquake traps them with a group of spiders, asking them to stop.
3: Derpy and Carrot Top flee deeper into the catacombs where they come across a kind and graceful unicorn, telling them to follow her to safety. The two don't notice the inscription on the wall. The spiders seem to retreat in fear of the unicorn's presence.
4: The small group are pursued by timber wolves as they sail up an underground river. Carrot Top seems transfixed by the unicorn's beauty and voice, while Derpy is more curious of the ruined city.
5: The trio approach an ancient set of doors. Derpy grows suspicious of their ally, seeing the carvings of the stellar sisters guarding over the tomb. Carrot Top, however, is hypnotized and opens the door to the tomb. The unicorn princess vanishes.
6: As the illusionary unicorn disappears, Carrot Top stumbles hypnotically into the cave. Derpy attempts to intervene, only to be stopped by skeleton ponies. The Ice Queen releases herself from her ancient throne that has served as her prison for over two thousand years, allowing her to regain her physical form and trap Carrot Top in her place. The skeleton ponies quickly rush Derpy tearfully out and away from the city.
7: Prince Fangor of the skeleton ponies casts a spell upon Derpy and his subjects to protect her from the Ice Queen's cold and hypnotic spell as they fight their way out of the city.
8: The Ice Queen finalizes her physical manifestation, feeling her power beginning to return to her with the release of her physical body. So long as throne remains intact and another imprisoned, her power can continue to escalate.
9: Derpy confronts the Skeleton King, angered by the abandonment of her friend. Derpy is recognized as the Flame Queen as foretold in prophecy, and is insisted to be the one to lead the skeleton army against the Ice Queen and her legions.
10: The Ice Queen gathers her power, intent on taking revenge on Equestria and Celestia and Luna for her long imprisonment.
11: Strategists assemble to plan for the upcoming battle. Derpy wonders what the Ice Queen might be after, and the Elder Council explains...
12: ...that the Ice Queen was once a great and power witch of the Frozen North who sought to rule over all the realms with her power over winter. Seeing to bring about an eternal Ice Age, she was stopped by the Stellar Sisters and imprisoned within her own throne; one soul bound to one artifact. Derpy suggests they let the main army engage hers while Derpy, the only one who can destroy the throne, sneaks behind their lines and rescues Carrot Top.
13: The Skeleton King and his spider allies ready for battle.
14: Derpy and her small strike force wait for their enemy's passage...
15: The battle is joined...
16: The Ice Queen has anticipated Derpy's maneuver, and claims that all flames shall be snuffed out eventually, and proceeds to do battle with her and her strike force.
17: The battle rages on...