Trade Ya!

Trade Ya! (spelled as Trade Ya by some sources) is the twenty-second episode of the fourth season of My Little Pony Friendship is Magic and the eighty-seventh episode overall. In this episode, friendships are tested when a trip to the Rainbow Falls Traders Exchange goes wrong.

Plot
Twilight Sparkle and her friends arrive at Rainbow Falls for the Rainbow Falls Traders Exchange to trade various items. As the official princess representative for the Exchange, Twilight finds a large welcoming party waiting for her.

Each of the seven friends are at the Exchange with various prospects in mind: Spike seeks to trade a mint condition Power Ponies comic book for another; Rainbow Dash hopes to acquire a first-edition copy of Daring Do and the Quest for the Sapphire Statue; Fluttershy wants to trade a bear call for a bird whistle; Applejack and Rarity seek out rare, vintage items and decide to pool together their trade stashes; and Twilight herself hopes to trade away some of her old books.

"That's not worth anything to me."

At a trading stand owned by a collector of Daring Do merchandise, Rainbow Dash finds the first-edition book she seeks. However, all she has to trade for it is an old, rusty horseshoe, which the collector refuses to accept. The collector only agrees to trade the book for an orthros owned by a dealer of ancient beasts.

Elsewhere, Applejack and Rarity each find a vintage item they want, but each item costs all of their goods. Applejack seeks a pie tin that Rarity visibly disapproves of, and Rarity seeks a brooch that Applejack notes looks no different than the one she's currently wearing. Tensions rise as the two ponies argue over each other's prospective trades.

Rainbow Dash and Fluttershy approach the ancient beast dealer, but he refuses Rainbow's rusty horseshoe as well. When the orthros breaks the dealer's lamp, he agrees to trade the orthros away for a new lamp. Thus, Rainbow Dash and Fluttershy approach Stellar Eclipse, a trader of Discord-shaped lamps, who agrees to trade one of his lamps for an antique chicken statue. A trader of antique chickens agrees to trade one for a crystal chalice. Rainbow and Fluttershy find a trader of crystal chalices who, ironically enough, agrees to trade one for Rainbow's horseshoe. Unfortunately, as soon as the trade is made, the chalice shatters in Rainbow's hooves.

Meanwhile, Pinkie Pie stops Twilight from trading away all her books for a young filly's broken quill, enforcing the rule of the Traders Exchange that a trade is only fair if both ponies end up with something they want. Because she doesn't have any plans to trade her own possessions, Pinkie decides to help keep Twilight from making the same mistake, and sets up a booth to promote the books as "official princess merchandise", which draws in a large crowd of ponies.

Rainbow Dash and Fluttershy glue the crystal chalice back together and bring it to the antique chicken trader, hoping he won't notice its condition. The trader accepts and smashes the chalice with a hammer to finish a broken glass mosaic. Realizing they don't know what kind of chicken the lamp trader wants, Rainbow Dash sends Fluttershy to check while she remains by the chicken stand to keep other buyers away. The Pegasi fly over Applejack and Rarity, who are arguing for the other to get what she wants to prove themselves the better friend. Upon returning to the lamp stand with the antique chicken in tow, Rainbow and Fluttershy discover that Stellar Eclipse has gone on break, frustrating Rainbow Dash.

Back at Twilight's stand, Pinkie becomes something of an auctioneer and hypes up Twilight's books to the crowd of ponies. Twilight becomes uncomfortable with the attention, stating that no one should trade for her books simply because she's a princess. Pinkie acknowledges Twilight's feelings, but proceeds to mention to the crowd that the books were given to Twilight by Princess Celestia, exciting the crowd even more.

Rainbow and Fluttershy find Stellar Eclipse again, who is in line for oat burgers and refuses to do any trading until he's eaten one. Remembering that the Exchange ends at sundown, Rainbow and Fluttershy assist in making oat burgers and moving the line along faster.

Finally, Rainbow Dash and Fluttershy make the exchange for the orthros and make their way to the Daring Do stand; the two pass Applejack and Rarity along the way, who continue to bicker. The Pegasi find their path blocked by a crowd of ponies, and see the Daring Do collector beginning to pack away her untraded goods for the day. Fluttershy remembers her bear call, and uses it to scare the entire crowd away. In their haste to reach the stand, Fluttershy drops her bear call, which is lost among the returning crowd.

When the Pegasi finally reach the stand, the Daring Do collector tells them she no longer wants the orthros as she is frightened of the vicious creature, to Rainbow's outrage. Fluttershy asks the collector to reconsider, demonstrating her expertise at taming the canine. The collector agrees to give Rainbow the book on the condition that Fluttershy stays in Manehattan with them to help train the orthros. Fluttershy reasons she would need to leave Ponyville for countless moons, but reluctantly agrees for Rainbow's sake. Rainbow eagerly makes the deal and claims the book as her own, only to realize moments later that she has just traded away her friend.

Pinkie continues to promote Twilight's books, especially the "princess" aspect, and is about to make a sale until she mentions that the books made Twilight the princess she is. Realizing they have nothing to match such value, the ponies disperse. Twilight herself also realizes how much the books mean to her, as they—like Pinkie said—made her who she is. Suddenly, Rainbow Dash zooms onto the scene and pleads for Twilight to exert her princess authority and declare a trade unfair.

Twilight presides over a small trial to decide the fairness of the trade; because Rainbow Dash said the trade was fair, her hooves are tied. Rainbow Dash argues that the trade can't be fair because, though she wanted the book more than anything, nothing is worth more to her than a friend. The Daring Do collector is moved by Rainbow's words and calls the trade off. Rainbow Dash returns the book to the collector, and Twilight declares both the trial and the Rainbow Falls Traders Exchange closed.

In the end, Spike turns out to be the only one of Twilight's friends to walk away from the Exchange with an uninterrupted trade.