Nebulon Diggers Alliance Group 13-Z The Nebulon Alliance unites groups of squat miners across the Imperium, distributing skills and labour in the name of maximum profit. However, when an employee starts becoming troublesome, or when a High Lord needs a squat given special punishment, the Alliance assigns them to their graveyard shift: Group 13-Z. Unlike the other groups, this one is strapped for battle as they are sent to Necromunda, to claw its valuable resources away from the gangs and houses that run the planet.