Yellow Lantern

From the greatest Green Lantern to the Corps' greatest enemy, Thaal Sinestro's fall from grace can easily be attributed to his own hubris—but if you ask him, the real problem lies in the Green Lantern Corps itself and its creators, the Guardians of the Universe. After all, as far as Sinestro is concerned, everything he does is for the good of the universe.

Originally hailing from the planet Korugar, Sinestro once served as the Green Lantern of Sector 1417 and quickly gained recognition among the Corps for his ability to police his sector. However, peace came at a price. Sinestro's determination to preserve order caused him to act more as a dictator than a protector, conquering his own home planet in the process. Control became his means to an end, the true path to order in both his sector and the universe as a whole, and Sinestro did anything necessary to achieve it. It wasn't until then new recruit Hal Jordan learned of Sinestro's methods that the Guardians were informed and Sinestro was ejected from the Corps.

Steadfast in his belief of moral superiority and methods of maintaining order, Sinestro formed the Sinestro Corps, harnessing the yellow energy of fear, to not only combat the Guardians, whom he sees as the main obstacle on the path to intergalactic peace, but to also strengthen the Green Lantern Corps, including members such as For it is Sinestro’s opinion that the Green Lanterns have long since been held back by their creators.