After his defeat at the hands of Hal Jordan and Kyle Rayner, Sinestro retreated to Qward where he began building his own corps based off his yellow power ring and the power of fear, embodied by Parallax. The purpose of doing so was for Sinestro to form his own corps that would enforce his vision of order (using those beings that instil great fear), of which he had always been at odds with the Green Lantern corps, during his time as a member. He built this Sinestro Corps in secret, recruiting beings from all the sectors of the universe in the same way the Guardians of the Universe did for the Green Lantern Corps. Sinestro selected the Talokian Lyssa Drak to be the Sinestro Corps historian and chained her to the Book of Parallax.
The Sinestro Corps first appeared in 2007's Green Lantern: Sinestro Corps Special - which was written by Geoff Johns and drawn by Ethan Van Sciver.
The Sinestro Corps wields the power of the yellow light of fear out of the emotional spectrum. Members are chosen throughout the universe for their ability to instill great fear, leading to an army of nightmarish creatures wielding power rings. Serial killers, torturers, mass murderers, criminals. These are the beings who comprise the Sinestro Corps.
Their Central Battery is located on the planet Qward in the Anti-Matter Universe, Sector -1. Enslaved Qwardians are forced to construct their rings and serve the needs of the Corps. Founded by Sinestro, the Corps seeks to bring order to the universe through fear and oppression. Prominent Members included the Anti-Monitor who also became the Corps sole Guardian, Sinestro's rings also sought out Superboy Prime, Cyborg Superman. Parallax was also part of the Corps as it's emotional entity. Sinestro recruitment drive for the Sinestro Corps War also included the likes of Arkillo, Karu-Sil, and Lyssa Dark.
After the war, Mongul found a dying member of the Sinestro Corp and took his power ring for himself. He began collecting yellow power rings and set up his rival Corps - The Mongol Corps. He took his Corps to Sinestro homeworld of Korugar. In a showdown with Mongul for control of the corps Sinestro proved the victor and the Sinestro Corps was reunited once again.
Major Story Arcs
Sinestro Corps War
For its big debut, the Sinestro Corps forged alliances with the Manhunters, the Anti-Monitor and Superboy-Prime in a major offensive against the Green Lantern Corps and Earth. It was all part of Sinestro's plan to make the Guardians afraid enough to enact new laws, such as authorizing Green Lanterns to use lethal force. The Sinestro Corps engaged in huge attacks against Oa, Mogo and Earth. They killed many Green Lanterns in the process, but in the end, they were driven off and many of them were captured including Sinestro himself.
The Green Lantern Corps hounded them in the aftermath of the Sinestro Corps War. The Sinestro Corps was scattered and being pursued by Green Lanterns. The power rings looking for new candidates were also being chased down and later destroyed on Oa. On top of that, female members of the Corps were being taken by the Star Sapphire Corps and converted. Without leadership, the Corps was disorganized and on the run. This changed when a ring found and selected Mongul as its new bearer. He took advantage of Sinestro's absence to position himself as the Corps' new leader, invading the planet of Daxam and calling all members of the Sinestro Corps to meet him there. He declared himsef as the new leader and defeated Arkillo when challenged. Meanwhile, others still loyal to Sinestro freed him from the Red Lantern Corps. The Corps was divided between two leaders.
After their escape, Sinestro and the Sinestro Corps returned to Qward, revealing that there was a backup main power battery. Sinestro ordered his men to free the Sinestro Corps members imprisoned on Zamaron by the Star Sapphires and meet him on the darkside of Daxam's moon. After Sinestro attended to "family business," he planned to retake the Sinestro Corps from Mongul. In addition to those members imprisoned on Zamaron, Sinestro Corps members were also being held prisoner on Oa. Their power rings were held in containment along with other rings (abandoned due to casualty in war) that were prevented from finding new bearers. When Red Lantern Vice was freed from confinement in his sciencell, he attacked the Green Lantern jailer. Though the imprisoned members of the Sinestro Corps initially cheered him on, they find that he is just as likely of attacking them in his rage. During the jail break, Scar freed the yellow power rings and they found their bearers in the sciencells. Upon being reunited with her ring, Lyssa Drak claimed to once again be able to feel the Book of Parallax. She would stumble upon the Book of Black and be imprisoned in its pages by Scar. Now armed with their rings the Sinestro Corps joined in the battle with the Green Lanterns and Vice.
The Mongul Corps
The faction of the Sinestro Corps led by Sinestro planned an invasion of Zamaron, homeworld of the Star Sapphires, in order to retake the female Corps members that were held prisoner there. After being repelled from Daxam, Mongul's faction (which he renamed "The Mongul Corps") invaded Korugar. Sinestro's rescue attempt was interrupted by a Black Lantern attack, which he only survives through the arrival of Hal Jordan and Indigo-1, leader of the Indigo Tribe. Indigo-1 brought Sinestro to Korugar, so that he could finally confront Mongul. After a fierce battle, Sinestro overrides Mongul's rings, using them to imprison him within the yellow central power battery, thus regaining control of his Corps. When he left with Hal Jordan's group of light-wielders, he commanded his Corps to gather at Korugar and protect it while he is away.
Sinestro shut down his corps after he found out how they were terrorizing his home world of Korugar. He and Hal Jordan shut down the central battery and put all members in stasis. As of now, only two sinestro corps members remain. The Weaponer and Arkillo who now wears a new yellow ring forged by The Weaponer to be free of Sinestro's influence.
Powers and Abilities
Yellow Power Ring
Each member of the Sinestro Corps is located by a yellow power ring which seeks out individuals who have the ability to instill great fear. The power ring works much like the Green Power Ring, but creating yellow constructs rather than Green. These rings can be repowered with a yellow Power Battery, or through the power source located in the heads of the Manhunter Android.
Members of the Sinestro Corps must recite this oath when recharging their yellow power rings:
In blackest day, in brightest night,
Beware your fears made into light
Let those who try to stop what's right,
Burn like his power... Sinestro's might!
The Sinestro Corps Oath reflects their position as the antithesis of the Green Lantern Corps.
The Space Sectors
Booster Gold: Founder of the Sinestro Corps
In Geoff Johns Booster Gold #2 - 52 Pick-Up, Chapter 2: Leggo My Ego, due a ripple in the time stream, Booster Gold is sent to the past in order to prevent Sinestro, still a Green Lantern at the time (which also takes place before Hal Jordan receives his power ring) from confronting Guy Gardner, as Sinestro is told by Supernova that Gardner would replace Sinestro as the Greatest Green Lantern ever. Posing as an admirer of Sinestro from the future, Booster prevents Sinestro from interfering with the path of history by convincing Sinestro that he could never be replaced. As they shake hands and depart, Sinestro notices Booster's Legion Flight Ring, which Booster replies is a tribute to Sinestro that all people in the future follow. When Sinestro asks Booster why the ring is yellow and to which corps he belongs to, Booster replies "The Sinestro Corps" - to which Sinestro replies "Of course!" whilst twirling his moustache in his iconic way.
DC Universe Online Legends
The Sinestro Corps are wipe out by Brainiac.
Batman the Brave and the Bold
In Batman the Brave and the Bold, an alternate universe version of Sinestro wears a Sinestro Corps uniform and yellow power ring.
Green Lantern First Flight
In the animated movie, Green Lantern First Flight, Sinestro is shown wearing his Sinestro Corps uniform.
In the live action film, Green Lantern, Sinestro is a Green Lantern, but a scene after the credits shows him putting on a yellow power ring.
The Sinestro Corps are referenced in Mortal Kombat vs DC Universe Green Lantern ending.