Twilight Sparkle, a reclusive student of Equestria's ruler, Princess Celestia, is tasked with supervising a special event in Ponyville and to make some friends in the process. There, she meets fellow ponies Pinkie Pie, Applejack, Rainbow Dash, Rarity, and Fluttershy. However, she is too focused on trying to prevent an ancient prophecy involving an evil pony who was banished to the moon 1000 years ago, and would return during the "longest day of the thousandth year".
The evil "Nightmare Moon" is free from her imprisonment, vowing to shroud the world in eternal night, and Princess Celestia has gone missing. Twilight and the other ponies must find six magic stones called the Elements of Harmony, hidden in the mysterious Everfree Forest. Through every obstacle they face leading to the artifacts, Twilight discovers a secret that can unlock the Elements' power and relight the world.
Twilight receives two tickets from Princess Celestia to the Grand Galloping Gala, which leads to an argument among her friends who all want to go, each with their own personal reasons. As if things could not get any more complicated for Twilight to make a choice, she notices them doing her favors to get on her good graces. To make matters even worse, the population of Ponyville learn of the spare ticket as well.
With her big brother hurt, Applejack volunteers to harvest the apple crop in her family's orchard all by herself. However, she is too prideful and stubborn to accept any help from the other ponies. She gradually works herself to the point of exhaustion, causing problems when she promises to help the others around town.
Pinkie Pie and Rainbow Dash bond by playing pranks on the other ponies, but when Rainbow's old friend, Gilda the Griffon, shows up for a visit, Pinkie Pie becomes a third wheel. However, she soon notices Gilda displaying a mean streak towards other ponies. A Pinkie Pie-styled party may reveal who exactly is Rainbow Dash's true friend.
When a magician unicorn who dubs herself "The Great and Powerful Trixie" constantly boasts that she is the most magical pony in Equestria, Twilight Sparkle becomes convinced that she is a fraud.
A sleeping dragon's smoke is disrupting the skies of Equestria and Twilight Sparkle is tasked with getting it to leave. All of her friends are set to head to the dragon's lair, with the exception of the fearful Fluttershy, who is not used to the rocky terrain, much less a giant dragon. The timid Pegasus must find the resolve necessary when her friends are in danger.
During a thunderstorm, Twilight invites Applejack and Rarity to her house for a slumber party. However, the latter two have a hard time getting along after a recent argument, until an accident forces them to reconcile their differences so they can clean up the mess.
Twilight encounters the mysterious zebra Zecora, who occasionally visits Ponyville and is rumored to be a witch. When she and her friends display a range of bizarre symptoms the next day, they begin to wonder whether Zecora put a curse on them. Applejack's little sister, Apple Bloom, ventures into the Everfree Forest to find the truth.
Princess Celestia is coming to visit, and everyone in Ponyville is making sure everything is perfect for her arrival, especially Twilight. Unfortunately, trouble arises when a swarm of parasprites, adorable insects with ravenous appetites, invades the town. And they are multiplying by the second! Pinkie Pie claims to have a solution to this problem, but no one really knows why she is gathering various musical instruments to do it.
Winter comes to an end, and Ponyville prepares for an annual cleanup to make way for spring. Twilight wants to take part as well, and is willing to do so without the use of her magic in the name of tradition. Everything she tries ends in disaster, but an argument among the disorganized teams inspires her to find her own way to help.
A pony earns a cutie mark upon discovering his/her hidden talent or purpose in life. Apple Bloom's concern about her missing cutie mark sparks her to find a way to earn it before an upcoming party. She soon discovers, however, that she may not be the only "Blank Flank" in Ponyville after meeting two other young ponies.
Applejack and Rainbow Dash put their skills and sportsmanship to the test as they face off in an Iron Pony competition to see who is the better athlete. Who will be crowned the winner, and more importantly, how will the loser handle defeat? Later, they take part in a marathon event known as the Running of the Leaves, in which Dash must compete without the use of her wings. Can they both ensure a clean race without the competition getting the better of them?
Rarity wants to make dresses for her friends for the upcoming Grand Galloping Gala, then gets an idea of setting up a fashion show in Ponyville to display her work. The project becomes a stressing problem when she tries to make each dress specific to its wearer's taste. To add to the pressure, a representative of the fashion world has learned of the show and is coming to visit. Will she meet all of their expectations, or will it end in 'total fashion disaster'?
Twilight learns that Pinkie Pie has an unusual ability to sense happenings in the immediate future, known around Ponyville as "Pinkie Sense." Not willing to accept that all of the events her friend had predicted are anything but a mere coincidence, Twilight sets out to find the truth behind Pinkie's power and figure out the "doozy" she says is about to happen.
Rainbow Dash becomes increasingly nervous whilst preparing her performance for the Best Young Flyer competition (where she could win a day with her idols, the Wonderbolts), as she planned to perform a highly advanced aerial stunt known as the Sonic Rainboom.
When Sweetie Belle's extremely loud lullaby scares one of Fluttershy's chickens into the Everfree Forest, she, Apple Bloom, Scootaloo, and Sweetie Belle try to venture into the forest to try and rescue her from the dangers within.
After entering a talent competition, the Cutie Mark Crusaders believe the event will help them discover what they are meant to do in life. They hope that winning the contest will help them get their cutie marks, if they can keep from ruining each other's work.
To create jewel-encrusted clothing at the request of a famous pony, Rarity decides to find a new lode of gems with Spike's assistance. But when a group of creatures called the Diamond Dogs abduct Rarity and force her to find gems for them, Spike and the other ponies head underground to rescue her. In the end, who will be the one that truly needs saving?
When Rarity gets to meet a famous fashion photographer, she realizes that this is her chance to promote the dresses that she's been designing, but her idea backfires when the pony is more interested in Fluttershy, whom Rarity chose to model her dresses. Can the elegant unicorn maintain her composure without becoming too jealous? Can the meek Pegasus handle the spotlight and the eyes of the adoring public? Meanwhile, Twilight is faced with a dilemma of keeping secrets told to her by Rarity, Fluttershy, and Spike, with the help of Pinkie Pie.
The ponies separate and are caught in a dispute between a western town's settler-ponies and the native buffalo herd. Both sides have claimed the land as their own, and neither side is standing down. Can they find a way to prevent the inevitable clash?
During a visit from Princess Celestia, Fluttershy sees the Equestrian royal's seemingly sick bird named Philomena. Without the princess noticing, the pegasus takes the poor creature home and tries to take care of it, only to find that this job is much more difficult than with her other animals. The situation takes a turn for the worse when Twilight gets involved and Celestia and her guards notice the pet missing.
Apple Bloom, Scootaloo, and Sweetie Belle learn the stories of how Rainbow Dash, Fluttershy, Rarity, Applejack, Pinkie Pie, and Twilight Sparkle got their cutie marks soon realizing that all six of their stories have a common connection
Spike meets an owl Twilight befriends to help her with their work. He soon begins to feel threatened over the possibility that it will take his spot as the unicorn's trusted assistant. Driven by jealousy, how far will the baby dragon go to make sure it doesn't happen? His friendship with Twilight is at further risk when he hides the fact that he recently destroyed one of her books by accident.
After a successful party celebrating the first birthday of Gummy, her pet alligator, Pinkie Pie invites her friends for an "After Birthday" party the next day. However, they claim to have other errands to run, declining the invitations. She finds out these so-called "errands" are just an excuse to avoid the party. Have they grown tired of the pink pony's frequent celebrations, or is there something bigger involved?
After much anticipation, Canterlot's Grand Galloping Gala has finally begun. As Twilight and her friends take part in the festivities, only one question remains: Is it everything the ponies imagined it to be?
Credit to Wikipedia for Descriptions and Arlax96 for the Videos