Wonderous item, rare

This enchanted jade is set in a dark metal pendant and strung with a black leather band.

When you roll a 20 on your attack roll while wearing this amulet, the creature you hit must make a DC 14 Wisdom saving throw. On a failure, it becomes frightened of you for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the item's effects for the next 24 hours.