Ronova

Ronova, also known as Tuonetar by the Frostmoon Scions, is the Ruler of Death among the Four Great Rulers of the Heavenly Principles. As the Ruler of Death, Ronova governs over the laws of death in Teyvat. She has the power to freely define the form of death for any entity in Teyvat, or may even deny it altogether, such as when she cast the curse of immortality on the pure-blooded Khaenri'ahns. She is a god whose existence predates any Archon. She is an extremely elusive figure, and records dating back thousands of years have nearly no mentions of her. In the past, Ronova sang alongside the angels on high. At some point, she would come to prefer embracing the rotting bones of the mortal world, and expressed the desire to witness firsthand its creatures, their lives, and their deaths. She helped Natlan establish their rules and gave guidance to Yohualtecuhtin, Lord of the Night, in creating the Night Kingdom. She had done this out of an expression of love and act of reparation, but these actions were considered to be overstepping her authorities as a Shade and it displeased the Heavenly Principles. After being censured by the Heavenly Principles, she "succumbed to self-pity", no longer cared if others discussed her identity and became increasingly indifferent to the fate of the land. Before the Traveler enters Tenshukaku, the shadow of Ronova's wings can be seen behind the Raiden Shogun, suggesting that Ronova may have been present and met with the Shogun before the Traveler arrived.