Anouki

The Anouki are a race of fairly humanoid beings that have antlers like those of a reindeer and are found in the World of the Ocean King in Phantom Hourglass and the re-established land of Hyrule in Spirit Tracks. They prefer to live in very cold environments such as the Isle of Frost in the World of the Ocean King and the Snow Realm of Hyrule. An animosity exists between the sect of the Anouki tribe in the World of the Ocean King and the more menacing-looking Yook tribe, but the Anouki are largely the only race inhabiting Hyrule's Snow Realm in Spirit Tracks with the Yook nowhere to be seen. They have provided Link with aid on more than one quest, helping the Hero of Winds locate the Azurine in Phantom Hourglass and helping the Link of Spirit Tracks locate the Snow Sanctuary in order to restore the Spirit Tracks to the Snow Realm and reach the Snow Temple.

Phantom Hourglass
The Anouki make their debut in Phantom Hourglass, residing on the Isle of Frost that is located on the Great Sea in the World of the Ocean King. The enemy of the Anouki tribe is the more fierce-looking Yook tribe, and a peace agreement made 100 years before the events of Phantom Hourglass gave the Anouki the western side of the isle and the Yook the eastern side. The Anouki are small humanoid creatures, with antlers growing from their heads. Usually, they appear to have no warm hide, and have to wear fur clothes, suggesting that they are not indigenous to such a cold area as the Isle of Frost, though not much is known about their tribe's full history or their true anatomy. The Anouki are one of the three tribes who were originally given the Azurine, one of the Pure Metals needed to create the Phantom Blade, however the Azurine is kept in the Temple of Ice on the Yook's side of the isle. Link is tasked with navigating the eastern half of the isle in order to reach the temple and retrieve the Pure Metal, though he is able to do so with the assistance of the Anouki.

It is known that the Anouki are honest people and never lie, as compared to the Yook, who have the opposite reputation.

Spirit Tracks
The Anouki reappear in Spirit Tracks, living in Anouki Village in the new Hyrule's Snow Realm after moving from the Isle of Frost. The Anouki have a monster infestation to deal with, and the chief Honcho requests that Link pair off the villagers into squads to fight back against the beasts. However, the Anouki of Hyrule are very fickle, only working with those meeting their specific requirements. With the assistance of the Anouki tribe, Link is able to successfully locate the Snow Sanctuary to meet with Steem and fully restore the lost Spirit Tracks of the Snow Realm in order to reach the Snow Temple.

One of the Anouki, Noko, works at the village's spring, creating Mega Ice, an ice so cold it can freeze lava. It is necessary to transport at least some of this ice to complete the game, as parts of Goron Village are blocked off by active lava flows.

Trivia

 * The name "Anouki" may be based on the word "inuk", which is an Inuktitut word for "person".
 * In both Phantom Hourglass and Spirit Tracks, the initial encounter with the Anouki presents Link with a logic puzzle. The puzzle in Phantom Hourglass is a type of Knights and Knaves puzzle, while the puzzle in Spirit Tracks is a type of puzzle more akin to a logic grid puzzle, in which Link must determine the set of pairings that satisfies all of the conditions given.
 * It isn't mentioned who told the Anouki that they couldn't "crash [on the Isle of Frost] forever". However, as the Yook are nowhere to be seen in the re-established Hyrule, it is possible that the Yook drove the Anouki out some time before Spirit Tracks and now have the island to themselves.