Korra

She's the master of all four elements, as well as the human embodiment of Raava, the spirit of light.

She knows all four primary bending arts, as well as the sub-skill of earthbending known as metalbending, although her preferred style is waterbending.

Korra was born in the year 153 AG to Tonraq and Senna of the Southern Water Tribe as an only child.

At the age of four she discovered her abilities and demonstrated them in front of the Order of the White Lotus, an organization tasked with finding the next avatar.

After her waterbending training was cut short by a snowstorm, a young Korra left her home to venture into the storm where she found a lone polar bear dog pup (who she would later name Naga) that had been separated from its pack. She decided to shelter the animal by waterbending a small igloo. The next day her father initially refused to allow her to keep the animal, but her waterbending teacher convinced him that Naga was Korra's animal guide.

When Korra was 17, she decided to sneak out of the White Lotus compound she has been living in on the south pole and travel to Republic City to learn airbending.

At first she proved to be very impatient and had difficulty learning but after becoming a professional pro-bender, she quickly mastered many airbending techniques.

Yet it would take having her bending temporarily removed while fighting a radical anti-bender before she was actually able to airbend.