Sebor's Nightmare is a Legendary belt in Diablo III. It requires character level 31 to drop. The special property is hardly usable in combat, and does not benefit from runes and enhancements of the player's skills. It works regardless of the player's class, however, and has roughly 70 yards radius. Obviously, in Greater Rifts, this belt is entirely useless. It shows best results while leveling, in areas full of weaker foes.