Vorpal

Legendary weapon property

Components: Masterwork exotic weapon that deals slashing damage

When you make an attack against a creature with this weapon and score a critical hit, that target takes an extra 4d8 slashing damage. Then roll another d20. If you roll a 20 on the second roll, you cut off one of the creature’s heads. The creature dies if it can’t survive without the lost head. A creature is immune to this effect if it is immune to slashing damage, doesn’t have or need a head, has legendary actions, or the GM decides that the creature is too big for its head to be cut off with this weapon. Such a creature instead takes an extra 6d8 slashing damage from the hit.