At the end of the war with the Sinestro Corps and after being banished from the Guardians of the Universe for their individuality, Ganthet and Sayd started the Blue Lantern Corps by creating a Blue Power Ring out of their hope for the future. The Blue Lantern Power Rings are powered by the emotion of Hope. While an entirely separate corps they are meant to aid other benevolent wielders of the emotional spectrum rather than replace them.