Asmoday

I'm the Sustainer of Heavenly Prínciples. The arrogation of mankind ends now... ... Outlander! Your journey ends here!

"The Sustainer of Heavenly Principles" was one of the gods that presided over the continent of Teyvat. Her responsibility was seemingly to ensure adherence to the "Heavenly Principles," a set of unclear divine laws that mortals and gods alike had to abide by unless they sought retribution. Eventually, an advanced human nation called the Kingdom of Khaenri'ah rebelled against the Heavenly Principles and was destroyed by the gods. A pair of twins who travelled across the stars were horrified by Khaenri'ah's destruction and tried to leave Teyvat. However, the Sustainer barred their path.

The Sustainer introduced herself to the Travelers and proclaimed that humanity's arrogation would end. The god tried to ensnare the Travelers with her power, but they avoided her attack and prepared to fight. The Travelers weaved through the Sustainer's spatial cubes and tried to strike the god down, though she blocked their combined attack. The Sustainer then absorbed both siblings using her cubes, and sent them down to Teyvat with their world-travelling powers stripped from them.