Domain Expansion

A number of times equal to your proficiency bonus you can create a Domain with a radius of 10 times half your proficiency bonus. All creatures the caster deems hostile will have disadvantage while in the domain and must pass a DC 15 constitution saving throw to exit the domain. You can designate a number of targets in the radius equal to their proficiency bonus to be marked for death. If an ally reduces a target to zero hit points the target regains hp equal to the damage dealt and the caster regains half of that amount. If you reduce a target to zero hp then you regain hp equal to the damage dealt and all allies recover for half that amount and the effect ends.