Carnage Blast

As an action, choose 1 target, that target makes a constitution saving throw. Upon failure the target takes 3d10 necrotic damage, half on success. If the target is reduced to 0 hit points as a result of this spell the target explodes dealing damage to targets around it. If the target explodes all creatures within a 15ft rd must make a dexterity saving throw or take 3d8 necrotic damage, half on success. At higher levels the spell does +1d10 on the target creature per spell level above 2nd. the explosion's damage does not increase.