Rumor has it that we won't see Green Lantern in the new DC Cinematic Universe until the Justice League film, and what better way to introduce him than bring in his arch-nemesis, Sinestro, as well? Sinestro is the mentor of Hal Jordan and a former Green Lantern who was thrown out of the Green Lantern Corps. for abusing his power. He was banished to the Antimatter Universe planet of Qward, which was ruled by a race of warriors and scientists who hated the Green Lanterns. There, Sinestro rallied them to his cause, and created a yellow Power Ring that harnessed the power of Fear. Later, Sinestro created the Sinestro Corps., and gave yellow Power Rings to the most feared and savage warriors in the universe. He may be a primary foe of Hal Jordan's, but he's one of the deadliest adversaries the Green Lantern Corps. have ever faced, and could easily give the Justice League a run for their money.