Hammer of Witches

Weapon (warhammer), rare (requires attunement)

When you hit a fiend or an undead with this magic weapon, that creature takes an extra 1d8 radiant damage. If you reduce the creature to 0 hit points with this damage, it is utterly destroyed and cannot be brought back by any means, and the sudden surge of righteousness fills you with power, allowing you to spend one Hit Die to regain hit points, as if during a short rest. While holding this weapon you have advantage on saving throws made to avoid becoming frightened by fiends or undead.