Push and pull, yin and yang, La and Tui are the Ocean and Moon spirits, respectively. La and Tui came to the Earth as mortals very near the beginning, in order to help humans and provide balance to Nature. La and Tui now live in a pond in a shrine behind the city of the Northern Water Tribe, circling each other for eternity. La is a black koi fish with a white spot on her forehead and Tui is a white koi fish with a black spot on his forehead. Admiral Zhao burned Tui in a rage to stop the Northern Water Tribe (Episode 20). Tui died, the moon disappeared (along with color), and waterbenders lost their abilities. Yue was present with many other characters when Tui died, and she revealed that when she was an infant, her father took her to La and Tui to cure her of a sickness. Her hair turned white, and part of Tui became her soul. Yue sacrificed her life to restore the Moon Spirit, and the balance of Nature returned (with the moon). This occurrence has left many questions - did Yue replace Tui, did Yue become Tui, were the two always the same thing, or was Yue half-human and half-Tui? Is there anything left of Tui in the new Moon Spirit? Should the new Moon Spirit be called Tui or Yue? What gender does the Moon Spirit have now, considering Tui is masculine while Yue was a woman? Whatever the case, while Yue was restoring the Moon Spirit, Aang and La combined to become a massive koi spirit made of water that finally rid the North Pole of the Fire Nation. The Moon and Ocean Spirits now peacefully circle each other in their pond once again.