Radiant Soulpiercer

Weapon (any polearm), uncommon
  Crafted to aid angels in their war on evil, soulpiercer weapons are able to appraise the soul of any creature they strike, detecting whether they are good or evil. A creature the weapon detects as evil is struck with radiant retribution, while the weapon attempts to prevent damage to good creatures. As well as as a means of assuaging a creature’s alignment, this mechanism protects angels should they ever be disarmed and have these weapons used against them.
  Alignment Assault. When you hit an evil creature with soulpiercer, it takes an additional 1d6 radiant damage as the weapon flashes in a bright burst of radiant energy. When you hit a good creature with soulpiercer, the creature has resistance to your attack’s damage as the wings at its head flare out, preventing deep penetration. Creatures protected against divination magic do not trigger either of these effects.
  Rare variant: You have a +1 bonus to attack and damage rolls made with this magic weapon. Increase the additional radiant damage to 1d10.
  Very rare variant: You have a +2 bonus to attack and damage rolls made with this magic weapon. Increase the additional radiant damage to 2d6. The weapon gains the Cleanse Evil property.
  Cleanse Evil. As an action you can speak the weapon’s command word as you launch the spear, which flies around you piercing evil creatures. Make a melee weapon attack with soulpiercer against each evil creature within 30 feet of you. The weapon then returns to your hand. Once you activate this property, you can’t do so again until the following dawn.