*First facing off against Arkillo and then against Sinestro himself, the evil Mongul, onetime leader of the Sinestro Corps, plays a pivotal role in the events of Blackest Night. *Source: dccomics.com
*Mongul, Son of the galactic tyrant of the same name, violently entered the ranks of the Sinestro Corps. He quickly sought command of the Corps in Sinestro's absence, and brutally tore it from the hands of Arkillo. Relocating the Corps to Korugar, Mongul employed wholesale slaughter to subjugate that race, in direct challenge to Sinestro.
Upon Sinestro's return during the events of the Blackest Night, he proved once and for all that he was the one true leader of the Corps, banishing Montul to the heart of his central Power Battery to suffer for an eternity. *Source: Back of Package