Curse of Porosis

Summoning the power the void the caster erodes the very bones of his foes. Each creature within the area of effect must make a Constitution saving throw. On a failed save, each creature takes 10d10 necrotic damage and are slowed indefinitely (A greater restoration spell will lift the effect). On a successful save each creature takes half damage. Any creature killed by Curse of Porosis is reduced to dust.