Vorpal Busters

Weapon (Any Melee Bludgeoning Weapon with a damage die above 6), Legendary, (Requires Attunement)

You gain a +3 bonus to attack and damage rolls made with this magic weapon. In addition, the weapon ignores resistance to bludgeoning damage.

When you attack a creature with at least 1 head, and roll a 20 on the attack roll, you strike with such force the head instantly splatters and is destroyed. The creature dies if it can't survive without it’s Head. A creature is immune to this effect if it is immune to bludgeoning damage, doesn't have, have multiples of, or need a head, has legendary actions, or the GM decides that the creature is too big for its head to be destroyed. Such a creature instead takes an extra 6d8 bludgeoning damage from the hit.