Fiends and undead take an extra 2d6 radiant damage when hit with this weapon. When this weapon reduces a fiend or undead to 25 or fewer hit points, the creature makes a DC 15 Wisdom _saving throw_ or it is destroyed. On a successful save the creature becomes _frightened_ of you until the end of your next turn. While it is held, this weapon shines bright light in a 20-foot radius and dim light an additional 20 feet.