While wearing this amulet, you can speak its command word as an action to summon a vrock and the vrock will take half of the wearer hit points. The vrock appears in an unoccupied space you choose within 60 feet of you. It remains as long as you concentrate (as if concentrating on a spell), to a maximum of 1 hour, or until it drops to 0 hit points. It then returns to its home plane.
While summoned, the vrock is friendly to you and your companions. It obeys any commands you give it, no matter what language you use. If you fail to command it, the vrock defends itself against attackers and attack anyone nears it.
Moreover, if the amulet is used again in the next 7 days it will summon lesser demon (demon with the challenge rating of 5 or under from The Monster Manual) and there is a cumulative 50% chance that it will break.
Notes: Summoning
Comments