A Hearth's Warming Tail

"A Hearth's Warming Tail" is the third Christmas-themed episode of , produced and aired in the show's sixth season. The episode's plot references Charles Dickens' A Christmas Carol. It premiered on on May 14, 2016.

Summary
The episode opens in Ponyville as ponies decorate the town and Castle of Friendship for Hearth's Warming. Fluttershy and Rainbow Dash oversee the delivery of snow clouds, Applejack distributes baked goods to everyone, Rarity makes decorative hats, and there is a general feeling of happiness all around.

Twilight Sparkle is excited for Starlight Glimmer to celebrate her first Hearth's Warming Eve in Ponyville. However, Starlight doesn't share her excitement and would rather skip the holiday. She considers the day no different from any other and "just an excuse for silly songs and fun".

When Twilight tries to explain the holiday's importance, Starlight says she already knows the story of how Earth ponies, Pegasi, and unicorns came together to vanquish the windigos. Twilight, however, intends to read her a different story: her favorite holiday story titled "A Hearth's Warming Tale".

A Hearth's Warming Tale tells the story of Snowfall Frost (Starlight Glimmer), a powerful yet bitter unicorn who hates Hearth's Warming Eve and values studying and magic above all else. She lives alone in her Canterlot home applying her knowledge to the betterment of Equestria; her only company is her loyal assistant Snowdash (Rainbow Dash).

Viewing Hearth's Warming as a "menace", Snowfall doubts the holiday's origins and believes singing songs and being nice are a waste of time. After she unwittingly excuses Snowdash to leave early and enjoy the holiday with her friends, Snowfall voices her disgust and desire to skip Hearth's Warming altogether, so she gathers some ingredients and prepares a magic spell to erase the holiday from existence.

Just before Snowfall casts her spell, her actions draw the attention of the Spirit of Hearth's Warming Past. The spirit expresses her opinions on Snowfall's spell by taking her on a trip back in time. She explains that every choice one makes in life has its consequences, no matter how small.

In the past, Snowfall sees her younger self, bright-eyed and happy to be celebrating Hearth's Warming Eve. However, when her magic instructor Professor Flintheart finds her decorating the classroom, he voices his displeasure. He tells Snowfall that if she wants to become a powerful unicorn, she must cast aside all notions of fun and focus solely on hard work and studying. Shaken by Flintheart's harsh truths, Snowfall takes his advice to heart and changes her point of view, thus sowing the seeds that cause her to grow up to be the pony she is now.

Upon returning to her house, Snowfall is then visited upon by the Spirit of Hearth's Warming Presents (Pinkie Pie), who explains to her the thoughtfulness that comes with exchanging gifts with others. She takes Snowfall on a tour through present-day Canterlot and shows her all the presents that the present has to offer.

At Snowdash's home, Snowfall sees a party being enjoyed by everyone in town. She also overhears Snowdash and her friends talking about her behind her back and criticizing her motives. As the ponies inside enjoy the party, the spirit remarks to Snowfall that this will be the last Hearth's Warming Eve party Equestria ever has. Before Snowfall can ask what she means by this, the spirit vanishes.

Suddenly surrounded by snow and fog, Snowfall Frost encounters the Spirit of Hearth's Warming Yet to Come. Snowfall believes this spirit intends to show her a future Hearth's Warming Eve, but the spirit says there are no more Hearth's Warming Eves to show.

In this future in which Snowfall Frost succeeds in erasing Hearth's Warming Eve from existence, Equestria is blanketed in deep snow and plagued by windigos. Realizing the cold nightmare of a future that she could potentially create, Snowfall finally understands the holiday's importance and pleads with the spirit to know if these events can yet be altered.

Snowfall is returned to her home once again, and she sees that there is still time to change the future. She goes to Snowdash's party bearing gifts and a new appreciation for Hearth's Warming Eve, and the ponies openly welcome her.

Upon finishing the story, Twilight excuses herself to join the party downstairs and tells Starlight Glimmer that she can join if she wants to. A short while later, Starlight accepts Twilight's invitation and joins the party as well, learning to let go of the past and enjoy the present.

Songs

 * "Hearth's Warming Eve Is Here Once Again"
 * "Say Goodbye to the Holiday"
 * "The Seeds of the Past (part 1 & 2)"
 * "Pinkie's Present"
 * "Luna's Future"
 * "Hearth's Warming Eve Is Here Once Again (Reprise)"