The Southern Lights

"The Southern Lights" is the second episode of Book Two: Spirits and the fourteenth episode of the overall series. It had first aired alongside "Rebel Spirit" on Nickelodeon on September 13, 2013.

Overview
''Korra and Unalaq travel the deeper parts of the South Pole to open the mystical portal between the spirit world and the physical world in order to release the long-seen southern lights into the sky. ''

Sypnosis
Korra meets Unalaq and is told that she must travel to the very center of the South Pole to open the potential, ancientportal between the spirit and material world. She is accompanied by her father and Team avatar before the winter solstice is over so that she can restore the southern lights that once shined in the sky as they do in the Northern Watertribe. As the tension rises with Unalaq and Tonrak, the former pressures the latter to confess his oppposition against dealing with spirits as he ashamed recounts that how the then chief of The Northern Water Tribe  banished him to the Southern Water Tribe for incinerating a forest sacred the spirits, enraging them causing a rampage much like the one that occurred in the festival.

Trivia

 * It is revealed that Tonraq was banished from the Northern Water Tribe.
 * A conclusion is drawn that Unalaq was not suppose to govern the tribes but Tonrak, thus making both Korra royalty and the avatar.