Kyle Rayner was a struggling freelance artist when he was approached by the last Guardian of the Universe, Ganthet, to become a new Green Lantern with the very last power ring. Ganthet's reasons for choosing Rayner remained a secret for quite some time. Despite not being from the same cloth of bravery and fearlessness as Hal Jordan—or perhaps because of that—Rayner proved to be popular with readers and his fellow characters. Having continually proven himself on his own and with the JLA, he became known amongst the Oans as The Torch Bearer. He briefly operated as Ion after using the power of the entire Green Lantern Corps. He was responsible for the rebirth of the Guardians and the re-ignition of the Central Power Battery, essentially restoring all that Jordan had destroyed as Parallax.
Kyle Rayner was chosen to wield the last ring because he knew fear, and Parallax had been released from the Central Power Battery. Ganthet knew this and chose Kyle because his experiences dealing with fear enabled him to resist Parallax. Because Parallax is a manifestation of fear, and yellow, none of the other Green Lanterns, including Hal, could harm Parallax and, therefore, came under his control. Kyle taught them to feel and overcome fear so they could defeat Parallax and incarcerate him in the Central Power Battery once again.
Kyle became Ion, who is later revealed to be the manifestation of willpower in the same way Parallax is fear. During the Sinestro Corps War between the Green Lantern Corps and the Sinestro Corps, Ion was imprisoned while Parallax possesses Kyle. In Green Lantern (vol. 4) #24, Parallax consumes Hal Jordan. Hal Jordan enters into Kyle's prison, and with his help, Kyle finally escapes Parallax.
Afterward, Ganthet and Sayd trap Parallax in the Lanterns of the four Green Lanterns of Earth. Ganthet asks Kyle to give up his right to be Ion and become a Green Lantern again. Kyle accepts, and Ganthet gives Kyle a power ring. Kyle is outfitted with a new costume including a mask that looks like the one from his first uniform. Kyle is now a member of the Green Lantern Corps Honor Guard, and has been partnered with Guy Gardner.
Kyle now shows up mostly as part of the ensemble cast of Green Lantern Corps. Corps rookie Sodam Yat took over the mantle of Ion. Sodam has made an appearance in the Legion of Super Heroes Final Crisis tie-in Legion of Three Worlds as the last surviving Green Lantern/Guardian of the Universe.
Kyle is designated as Green Lantern 2814.4 within the Corps.[citation needed]
Kyle Rayner died in Green Lantern Corps #42 (Jan. 2010) after sacrificing himself to save Oa from an attack by the Black Lantern Corps. The following issue, Kyle is brought back to life by the power of a Star Sapphire who connects Soranik Natu's heart to his heart.