Sinestro: Year of the Villain #1

Lex Luthor assigns Sinestro to defeat a god-like race of aliens known as the Paragons that Luthor believes will be a threat to his plans. When Sinestro discovers that the Paragons are nearly invulnerable due to microscopic beings living inside them that repair any damage to their bodies, Sinestro must try an unusual approach to stop the threat.