Rao is a Kryptonian deity, symbolizing sunlight.
After Mon-El's sacrifice, Kara Zor-El devoted her life to her heroics as Supergirl, reconnecting with her Kryptonian heritage, as she started to meditate and pray according to the tenets of the faith of Rao. However, she wasn't the only one who was affected by this religion. Thomas Coville, an ex-lawyer saved by Supergirl on Flight 237, has found hope in his life once again and started gathering others saved by Supergirl. Using knowledge from a Kryptonian capsule he has found, Thomas created the Cult of Rao, spreading the Kryptonian deity's worship on Earth, although Kara Zor-El considered the ways of this cult to be heretical, misunderstanding Rao's message, primarily because Thomas intended to portray her as one of the deities of the pantheon. Despite this, she went back to the private worship of Rao herself, performing a prayer of the faith alone with the hologram of her mother. One night, in the bathroom, Samantha Arias looked in the mirror, she was horrified to see herself covered in strange symbols. She heard whispering behind her and turned around and was terrified to see a woman in a cloak standing behind her. The woman stated that she was born from Rao's fire. 
Rao is seen as a benevolent god, guiding his worshipers and giving them hope. Certain faiths, like the Cult of Rao, consider the earthly troubles and challenges part of Rao's test that his chosen must overcome. The Cult's mysterious benefactors intended to spread the idea of reigning in Rao's name to Samantha Arias and her daughter, Ruby Arias.
Powers and abilities
- Immortality: Due to him being a deity, Rao is presumed to be an immortal being.
- Sun/Light-related powers: Being a deity symbolizing the sunlight, Rao is credited with its powers.
- Omniscience: It is said that Rao has seen the path for each of his worshippers.