'Legendary sorcery associated with the Carian queen. Uses the caster as a vessel to incarnate a cold, dark moon, then sends it floating toward foes. The dark moon dispels all sorcery that touches it, and lessens magic damage negation of foes.' The Dark Moon is the heirloom magic of House Caria. Rennala learned it in her youth, when the snow-witch Renna of the cold north taught her ; Rennala then taught it to her daughter Ranni, who taught it to no one. It is not flashy. It does not burn or roar. It is a slow, low-lit projectile of pure cold, and it cancels every other sorcery it meets in flight. The dark moon dispels because the dark moon is older than the spells it touches.

'Sorcery said to have been used by the old snow witch. The snowy crone taught the young Ranni to fear the cold. Ranni was so unaccustomed to being afraid that she found the feeling addictive, and the snow witch's lessons were her cherished memory.' By the time the Tarnished meets her, Ranni has become a witch in her own right, her child-body inhabited by the soul of a Numen woman who killed her own flesh in protest of her destiny. The Dark Moon is the wedding-gift she carries into the Lord of the Frostmoon ending : the Lands Between, having known the Erdtree's fierce gold for so long, are taken into the cold and the distance and the dark instead. 'My Lord, my consort eternal,' she will say if you accept her ring. The cold she chooses is not death. It is exile far enough away that the Outer Gods cannot find them.