Divine Departure (legendary spell)

The Paladin or Cleric of Light Domain, ever connected to a God or Goddess. As a last resort to victory, you take your weapon imbued with Holy magic and sacrifice it to summon 3 mountain sized swords made of Radiant light that descend from the Heavens. To do this, cast a 9th level spell and perform a holy ritual and destroy your weapon. With all your might shout the holy celestial words as a barrier protects you and your allies as these swords fall from the Heavens