Saysoran was created by Justin Jordan and Diogenes Neves in Green Lantern: New Guardians: Futures End #1.
Five years in the future of the DCU, Kyle Rayner has mastered the power of the Life Equation and become more than just the White Lantern ---- he has become a being who can change men, worlds and the universe through sheer force of will, and burdened with the knowledge of a dark and predatory cosmos, resolves to use his power to bring peace to all life. Over the years, he accomplishes this by visiting countless planets and altering the minds of all the inhabitants, driving away violence and anger from their minds, and leaving them only with the desire to live in happiness with their fellows.
On one such world, he fails to convert everyone, as a young girl named Saysoran resists every attempt to turn her mind and escapes from her family and friends, who all try to show her what they have been shown by the Life Equation. She boards a spacecraft for Kyle's cosmic abode, deep in space, and upon arrival hears Kyle's voice in her ear, telling her that he has arranged for her to find him. Kyle tells her that though his power is infinite and his knowledge unlimited, he is plagued by doubt, and that Saysoran possesses the one thing he does not: the perspective to judge his actions from outside.
When he manifests before her eyes, Saysoran calls him insane, and attacks him with weapons from the abode. Unharmed, Kyle admits that she may be right about him, and muses that the possibility of his insanity is part of the problem. He marvels at the fact that of all the billions upon billions of minds that he has turned, each possessing the ability to resist him, only she succeeded in doing so, and asks her why she would resist him if she saw the pain and suffering that exists throughout the universe. Saysoran angrily counters that she resists because Kyle has no right to decide the fates of others, and that everyone has to find their own version of happiness their own way.
Kyle reveals that his life is nearly over, as he will soon merge with the Source itself, and needs someone worthy to take the power of the Life Equation from him and carry on. He tells Saysoran that all of what she has experienced has been a test, to judge her suitability, and that he has found her worthy of the task. In a flash of light, he fades away, leaving only the white ring behind. His voice tells Saysoran that only she can judge him; that she can undo all he has wrought, or she can carry on from where he left off. He tells her that he cannot force her to accept the responsibility, and that only she can decide. As his voice fades, Saysoran slips the ring onto her finger, and ascends to become the universe's new White Lantern.