Manhunter

Involvement
When the Sinestro Corps wages battles in and around Metropolis City Hall, Manhunters under the crontol of the yellow ringed fear mongers are amongst their ranks.

Villains: A defeated, fallen Manhunter will ask you to locate Green Lantern rings from fallen GLs and bring them to him for destruction.

Trivia
Manhunters were originally responsible for policing the universe for the Guardians of Oa before the Green Lantern Corps existed.