Sodam Yat

Origin

Born and raised on the planet Daxam, the young Sodam Yat was fascinated by the stars and the worlds beyond his own, and rebelled against his xenophobic society when an alien named Tessog crash landed on Daxam. He and Tessog transcended their language barrier to become close friends, and Yat helped to protect and care for the wounded alien, until he was discovered by Yat's parents. They killed Tessog and brainwashed their son, convincing him that Tessog, like all aliens, was a menace to Daxamite society. Several years later, upon encountering Tessog's body stuffed and mounted in a museum, Yat's true memories flood back and he resolves to flee his planet. He manages to repair Tessog's ship, but prior to his departure he is met by a Green Lantern ring, which chooses him as its new bearer. Yat is unaware that he is the subject of a prophecy which heralds him as a great Green Lantern, but also as the sign of the end for the Corps.

Creation

Sodam Yat was created by Alan Moore and Kevin O'Neill.   

Major Story Arcs

Sinestro Corps War

Yat is called upon, along with several other new graduates, to aid in the fighting during the Sinestro Corps War. Arisia is set to watch him due to the prophecy, and he travels along with a number of other Lanterns to Mogo. There, he takes part in the fighting to defend Mogo against Sinestro Corps incursions. During the fighting Yat distinguishes himself, displaying uncommon skill in his defeat of numerous members of the Sinestro Corps. He is sent on the assault of Ranx, and shows himself to be a capable leader and skilled Lantern, single-handedly destroying the sentient city. He is then called to fight on Earth where he again takes the role of leader and impresses his fellow Lanterns. Upon the Anti-Monitor's arrival he challenges him himself. He is struck down several times, but manages to rally thanks in part to his Daxamite heritage, and survives the encounter thanks to the intervention of the Guardians. 

Ion

Yat is chosen as the new Ion following the infection of Kyle Rayner by the entity Parallax. His first opponent after his Ion transformation is Superboy-Prime. He and Prime wage a fierce battle that suddenly turns against Yat when he realizes his weakness to lead upon being weakened by lead shielding. Despite his efforts, he is defeated by Prime. His exposure to lead during their fight leaves him dependent on his ring to keep the lead poisoning at bay. He later receives training from Kyle Rayner in the use of his Ion powers. He and Rayner fight the newly-escaped Alexander Nero, and Yat displays newfound proficiency with his powers, ultimately winning the battle and defeating Nero. 

Final Crisis

Yat is informed of the death of Orion on Earth, and later of the fact that Hal Jordan has been accused of murder. He attends Jordan's trial alongside Arisia, and is among the honour guard that is attacked when Kraken reveals that it is she who is under the influence of a dark god. Yat then volunteered to join Jordan on Earth to confront Darkseid. He later joined the Corps in standing before the Monitor Nix Uotan, fighting Mandrakk, and repairing the Multiverse.

Legion of Three Worlds

A future version of Yat, the last surviving member of the Lantern Corps, is encountered by Mon-El and Shadow Lass on the ruined remains of Oa. Broken by past failures and the deaths of all his fellow Lanterns, Yat is reluctant to aid the pair in their fight against Superboy-Prime. They eventually manage to convince him, and he absorbs the power of all the rings that lie scattered across Oa and goes to confront Prime and the Legion of Super-Villains alongside his new allies. Following the battle, he decides that the universe needs continued protection, and restarts the Lantern Corps.   

Ring Quest

Yat is charged, along with a number of other Lanterns, to travel into the Vega System and capture several Sinestro Corps rings which haven't yet found bearers. This quest leads Yat to the planet Sedas, where he and Arisia are captured by Duel and Mongul. They are subjected to the black mercy, but are rescued by the other Lanterns. Before they are able to fully recover, the Lanterns are attacked by Mother Mercy. Yat, still suffering from the effects of the black mercy, manages to injure Mother Mercy, earning the Lanterns a brief reprieve. The Lanterns then negotiate with Mother Mercy, who releases both Yat and Arisia from the black mercies. Attacked by Mongul yet again, the Lanterns are secretly aided by Mother Mercy, and Yat and the others manage to defeat Mongul and Duel.   

New Krypton

Yat is sent to Earth to work alongside Hal Jordan, who is assessing the threat posed by the newly freed Kryptonians of Kandor. He joins the Earth Lanterns in their tour of New Krypton and helps to capture a saboteur before returning to his hunt for Sinestro Corps members. Shortly afterwards he attempts to return to Earth to inform Mon-El about the truth of Daxam's history, but is stopped by Tellus, who warns him that continuing on may bring about a chain of events that allows evil to win. Yat entrusts the knowledge crystals about Daxam to Tellus, and returns to Oa.  

Sins of the Scarlet Sapphire  

Yat is summoned to act as an escort and guard for some members of the Guardians during their negotiations with the Zamarons. Yat is instructed that, should negotiations fall through, he is to lay waste to the Zamaron capital and the Star Sapphire Central Power Battery. When no hostilities result from the meeting, he returns to Oa. 

Emerald Eclipse

Yat is distracted from his tasks by the sudden arrival of his mother, who crash lands Tellog's repaired ship near where he is holding a prisoner in a sciencell. She informs him that Daxam is under siege from members of the Sinestro Corps, and begs his intervention. He initially refuses, angrily explaining how his parents had treated him and Tellog, and claiming that their own xenophobia was responsible for their having no allies to turn to. Eventually he relents, but only after forcing his mother to express gratitude to Tellog. He and Arisia travel to Daxam, where he finds his father advocating mass suicide rather than allowing Daxamites to fall into the hands of the Sinestro Corps. They rescue these Daxamites, and confront and kill several Sinestro Corpsmen, despite Arisia's vocal opposition to lethal force. Yat then confronts Mongul on his own, and is prevented from accessing his Ion powers due to the influence of the Guardian Scar. He is able to unlock partial Ion powers only by allowing himself to be struck with one of Mongul's energy blasts. He manages to defeat several Sinestro Corpsmen, but with his powers rapidly fading he is forced to sacrifice himself. Allowing himself to part with his ring to prevent Guardian interference, he plunges into the sun. He changes the red sun to a yellow one with a powerful release of energy, allowing the Daxamites to use their new powers to fight off the remaining invaders. Trapped in the sun, Yat apparently dies.

Brightest Day 

An unknown being approaches Daxam's sun, where Yat remains, apparently dead, and removes the Ion entity from him. Yat plunges out of the sun to the surface of Daxam, alive but unconscious. He is located and rescued by a small group of Daxamites who revere him for the great sacrifice he had made for them. They warn him of the plan amongst some Daxamites to locate him and throw him back into the sun in the hopes of regaining their powers. Yat announces that, in order to fix the xenophobic Daxamite society, they must first make the whole universe a better place. He leads his followers on a mission to bring the Guardians to justice for their sins. 

Powers and Abilities 

As a Daxamite, Yat possesses all the powers inherent to his race. This means that, under a yellow sun, he possesses superhuman strength and stamina, invulnerability, longevity, flight, super speed, super breath, super hearing, and several varieties of superior sight. Yat also possesses notable engineering skill. He is a capable hand-to-hand fighter. His Daxamite heritage renders him vulnerable to lead.
 
As a Green Lantern, Yat possesses a Green Lantern ring which can be wielded to a variety of effects, and is essentially constrained only by his own creativity. He can use the ring to, among other things, create energy constructs, wield energy blasts, and heal himself or others. Among other functions, the ring operates as an assisting artificial intelligence, a means of spaceflight, and a communicator. 
 
As Ion, Yat had access to powers similar to those of a Green Lantern, but on a greater scale. As Ion, he possessed the combined energy of all of the Guardians, and had theoretically limitless abilities. Known abilities possessed by Ion-wielders include the ability to raise the dead; to manipulate or alter reality, time, and matter; and to be functionally immortal.