The Night King should be a northerner and brandon stark. After Bran became a three-eyed crow, he constantly traveled through time and space to find a way to stop the night king. In history, many wolves with the strongest resistance to alien ghost teams are called Brandon, which is very telling. The true identity of the night king is most likely to be worn back to Bran, captured by the son of the forest, and then made into a strange ghost.
The night king should be a northerner, even a wolf, and has an unusual connection with Bran. Give full consideration to Addo's time cycle storyline, no matter whether the night king is in the past or in the future, one section of a ring is undoubtedly more exciting than that of Addo.
Obsidian inserted into the cardiovascular system of the ancestor "Stark", creating a strange ghost. Before the ancestors arrived in Westeros, the son of the forest ruled Westeros, and with the bronze weapons and equipment produced by the ancestors' invasion, the son of the forest armed with obsidian was unable to resist. As many weirwood in the south were cut down by their ancestors, the son of the forest was forced to go to the north of Kanazawa. The son of the forest was very worried, and finally he turned to magic. They implanted obsidian into the cardiovascular system of their ancestor "Stark" and created alien ghosts to resist the constant invasion of their ancestors. With the birth of alien ghosts, the ancestors stopped invading, but the sons of the forest found that the energy of alien ghosts was beyond their control.
With the existence of the Great Wall in Wan Li, the alien ghosts can't reach an understanding with their ancestors through the last son of the forest and jointly resist the uncontrollable alien ghosts. They also used magic to build the Great Wall in Wan Li and sent alien ghosts to the far north. Because of the existence of the Great Wall in Wan Li, alien ghosts could not pass through, which made Westeros enjoy peace for thousands of years until the dragon slayer appeared. With the passage of time, the son of the forest finally faded, but the alien ghost still exists, and the alien ghost still remembers the meaning of his existence, "fighting against his ancestors."