Rerir

He is one of the Five Sinners of Khaenri'ah and the leader of the Wild Hunt.

Realizing that he could use the power of the kuwahaki to restore his original form, as his power from the Abyss was far superior to it, Rerir kidnapped the Guardian of Light, Sucy, by assuming her form to convince the Traveler to repair Aino's Boom and Explode Kuwahaki cannon, and then assumed Flin's form to kill Sucy. Later, he aimed the cannon at himself on the Star Sand Bar to restore his original form. The traveler and Flins fought him, and he claimed that humans could not comprehend the power they wielded, but admitted that it would allow him to return. When the cannon fired at them, the Traveler and Flins were able to deflect some of the projectiles, and Ineffa had to manually lift the cannon to redirect it. Although Rerir managed to regain his form, he was enraged by the fact that it was an incomplete shell, and he estimated that he had regained only a fraction of his original strength. Furious that his plans had once again been disrupted, he attempted to attack them, but he was thwarted by Sandrone and Pulonia. Rerir defeated Pulonia with a few dirty tricks, but he couldn't kill the others because they teleported before he could grab them.

After this encounter, Rerir went in an unknown direction, but he soon realized that someone was following him, and he ordered them to show themselves. The person turned out to be Varka.

Seeking to discover the truth of Teyvat, Rerir sought out fragments of his power in various locations of the Wild Hunt, but they did not possess the power he sought. He then learned of the Traveler's arrival and, using his newfound abilities, managed to assume the forms of various individuals, including the Traveler's brother or sister. Additionally, he sought out the Moonlight Brain, but his plans were thwarted by Vilemina, who took it for the Fatui, as Rerir himself could not possess it as a ghost. Later, he tried to fight them in ghost form on the Star Sand Bank, but after a brief battle, he was forced to retreat.

Rerir, along with Surtalogi, Rainedortir, Vedrfolnir, and Hroptamir, were considered the best of their peers when they lived in Khaenri'ah. He had an unnatural attraction to the moons beyond the False Sky. After gaining access to the power of the abyss, they chose not to use it to save their homeland and became known as the Five Sinners.

At some point after the cataclysm, Rheerir created the Wild Hunt and apparently entered the "reflection of the moon," which is considered a point of no return. As a result of his disappearance, the Wild Hunt began to spiral out of control. Eventually, Rheerir survived, likely due to a combination of the power of the abyss and Rona's curse of immortality, although his physical body was destroyed and scattered throughout the Nod-Realm. With his will intact, Rheer managed to piece together some of these components to create a disjointed ghostly form of himself. His main component, the heart, ended up in Flins' lantern.

The title of Reri is Moon Hunter or Man Who Hunts the Moon. Five hundred years ago, Reri and five other heroes teamed up to rescue Dain's brother from prison and stop Yrmine from destroying Teyvat. He was one of the most talented and respected heroes of his generation.

Cruel, vindictive, warlike, aggressive, and sometimes terrifyingly calm

In his physical form, Rerir has white hair. Black bandages cover most of his face, leaving only his right eye visible. A majority of his attire is covered in black bandages, and Abyssal power exudes from a majority of his exposed areas, barring his chest, manifested as red blots of energy.