Oogi

Oogi  is a flying bison owned by Tenzin and his family Appa is his dad. He is a descendant of a group of flying bison found by Avatar Aang after the species was thought to be extinct due to the Hundred Year War.

History
Oogi carried Tenzin and his family as they traveled to the Southern Water Tribe to meet the newly incarnated Avatar, at which point Tenzin informed her that he would be unable to train her due to his responsibilities in Republic City. Oogi was also used to fly the family back to Air Temple Island.

Oogi later flew Tenzin and Korra back to Air Temple Island under the command of the airbending master.

When Korra went missing, Tenzin, Lin Beifong, and Team Avatar used Oogi to search for her.

Following an assault of the island by Equalist forces and the birth of Tenzin and Pema's fourth child, Rohan, the entire family fled their home on the trusty sky bison.

Following the defeat of Amon and the Equalists, Oogi was last seen sleeping peacefully in front of Katara's house in the Southern Water Tribe.

Trivia

 * The Laughing Buddha is often portrayed wielding a wish-granting fan, known as an oogi.
 * Oogi responds to the command "yip yip", just as Appa did.
 * Oogi has many more stripes on his back than Appa did.
 * When Sokka witnessed Katara and Aang in their relationship (as seen in The Promise Part 1 and Part 2), he stated that it gave him the "oogies".
 * Oogi appears to be Tenzin's personal sky bison.