Yak

Yaks are a species of bovine who live in Yakyakistan, a cold land north of the Crystal Empire and Equestria.

History
In the distant past, Yaks fought a war against the Dragons over the land that would eventually become Yakyakistan. Eventually, Yak Prince Ulysses and Dragon Lord Scintilla negotiated a peace between their peoples, and Scintilla was declared an "Honorary Yak" in token of their friendship. Some time later, Prince Gruntwig would witness the Griffon-Pony land treaty, in which the Griffons sold a large parcel of land to Equestria. After the reign of Prince Dromius, Prince Crompus would witness a follow up to this treaty confirming that the Ponies had paid the agreed-upon sum to the Griffons. At some point, there was a Yak hero known as Yksler who wore a magical helmet, which later came into the possession of the Ponies.

At some point, the Yaks would become isolated from their various neighbors, with "hundreds of moons" passing without contact between them and Equestria. Princess of the Four Princesses of Equestria sought to end this, and reached out to Prince Rutherfod, inviting him to Ponyville. Relations initially went poorly, and at one point Rutherford even declared war on Equestria. Fortunately, was able to befriend the Yaks by sharing Pony culture with them, and a peaceful new relationship soon emerged. Things only improved after Pinkie Pie, attending Yickslurbertfest, brought in her friends to help clean up an avalanche without the Yaks having to request their aid, and was thus honored as an Honorary Yak and Friendship Ambassador to Yakyakistan.

The Yaks had more difficulty in befriending their other neighbors, and was forced to negotiate a peace between them and the Griffons after the two nearly went to war after the Griffons scored a single point against the Yaks during a boffyball game. Fortunately, the Ponies continued to build bridges with the Yaks, with Shining Armor and Prince Blue Blood negotiating a trade agreement between their two peoples, and Celestia inviting Rutherford to events that sometimes included other world leaders. Pinkie Pie's Honorary Yak status proved a sore point, however, and sparked a second Dragon-Yak war as Dragon Lord Ember led her people against the Yaks. Fortunately, a Dragon raised by Ponies, was able to get the Yaks, their Pony allies, and the Dragons to cease fighting and come to a peaceful end to the conflict.

A number of Yaks also attended the Convocation of the Creatures at Mount Metazoa, with their participation in the Griffon-Pony land treaty proving vital to preventing a large portion of Equestria from being seized by the Griffons. At the invitation of Celestia, a young Yak, Yona, was chosen to represent the Yak's at Twilight Sparkle's School of Friendship. This nearly proved disastrous, as an incident involving Yona and the other students led Chancellor Neighsay to close down the school, and the students' subsequent disappearance nearly moved Rutherford and other leaders to declare war. Fortunately, the students were found, and Twilight and Celestia were able to assuage the leaders' fears.

When the Legion of Doom attempted to conquer Equestria, Yona rallied the Yaks to their aid. A considerable force of them took part in the final battle, using their strength to throw the villains off balance. Several yaks later attended Twilight Sparkle's coronation as Queen of Equestria. Years later, several would be seen either visiting or apparently living in Canterlot and Ponyville.