- "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!" —Sinestro Corps oath
The Sinestro Corps is an inter-galactic force dedicated to inducing fear into any and all sentient life in every form. Established on the planet Qward by renegade Green Lantern Sinestro, Sinestro Officers are chosen for their ability to induce great fear and are given a power ring fueled by the fear of other individuals.
Created to offset and combat the Green Lantern Corps, each member has a great deal of autonomy as to their methods in their tasks. The individual Lanterns are responsible for arranging their replacements if they are near retirement or death. If the Lantern dies before that obligation is met, the ring will find and seek another to be trained on its own.
The Green Lantern Corps and Sinestro Corps have both arrived in the Metropolis Historic District. Both corps have been experiencing strange power disruptions with their power rings, suspecting that the cause lies with the other.
- Deep within S.T.A.R. Labs, Brainiac seeks to control experimental devices that will allow him to harness the power source behind the Lantern Corps' rings. This attack throws the Lantern Corps into chaos, and players must join a fragile truce between the Green Lantern Corps and the Sinestro Corps to bring the powerful devices back under S.T.A.R. Labs control.
- As a hero, you will team with the Green Lantern Corps and battle the Sinestro Corps in the streets surrounding Metropolis City Hall. Once inside City Hall, you will join the fight alongside John Stewart to defeat Sinestro.
- Villains aid the Sinestro Corps in their fight against the Green Lantern Corps. Ultimately villains will fight John Stewart with the aid of Sinestro.
- Later on, they'll aid the Sinestro Corps again to combat the Green Lanterns. Villains must free Sinestro Corpsmen being held captive by the Green Lanterns and help reconstruct Manhunters before fighting Wildcat, Hawkman, Hawkgirl and Green Lantern (Alan Scott) in order to free Sinestro from the Justice Society of America while being aided by the Sinestro Corps.
- If the player chooses Light as power, and has the Fight for the Light DLC, the player will use the yellow power of fear and battle as a Sinestro Corpsman.
- The Sinestro Corps first appeared in Green Lantern #10 (May, 2006)
- The corps' power is fueled by Parallax; an entity that is the embodiment of fear.
- Batman was nearly inducted into the Sinestro Corps as their ring-bearer for Sector 2814 in Green Lantern vol. 4 #17 for his ability to "inspire great fear in others."