Deep in the Batcave™ vault, Batman™ has gathered various weapons in case one of his fellow Justice League™ teammates should ever go rogue. Amongst the contingency weapons is a Sinestro Corps™ power ring, recovered when Sinestro™ and his yellow lantern army attacked Earth. During the events of Forever Evil, the evil Power Ring and his Crime Syndicate attacked Earth-0. Theorizing Power Ring's ring of power had the same ineffectiveness against the color yellow as Green Lantern™, Batman put on the Sinestro Corps ring, and prepared for battle
