Long ago, the twin moons of Crius were guarded by two goddesses, Nisa and her sister, each representing a different aspect of the celestial night. Nisa embodied the shifting phases of the moon, her appearance and personality changing in sync with its waxing and waning. During the new moon, she was the goddess of misery and misfortune, bringing shadow and hardship. Yet, when the moon was full, Nisa became a radiant protector, offering Drinera's (the goddess of light) guidance and hope when darkness was overwhelming.

Known as "the goddess who hides her face," Nisa wears a mystical veil, which moves with the moon's phases, either revealing or concealing her face. As the moon waxes, her veil slowly lifts, revealing her features; during the waning moon, it covers her more completely, symbolizing the return to shadow.

However, Nisa was not the only moon goddess. Her sister, born from the darker, evil side of the moon, represented all that was malevolent and destructive. Upon her birth, she was slain by an army of Tatoe Tots, leaving only Nisa to govern the moon. The moon her sister had dominion over was shattered, and its remnants now form the glittering rings of Crius, a reminder of the darkness that once existed and the sacrifice that preserved balance.