Sarolis was the Green Lantern of Space Sector 3544.  While battling a renegade Sinestro Corps Soldier, Sarolis was fatally injured and soon discovered by the Indigo Tribe.  Using the Indigo Light of Compassion, their leader Indigo used her power staff to manipulate Sarolis' emerald energy aura, using it to suffocate the Lantern and putting Sarolis out of his misery.  Indigo then turned on the Sinestro Corps Soldier of Sector 3544 and used his own Yellow Light of Fear to create a monstrous energy construct to frighten him away.