Niruul, the Hollow Voice

Niruul, the Hollow Voice is a Void-aligned Psion Flayer of the Red Legion and the quietest of three Psion sisters who lead the faction. Together with her sisters she used the Sundial to split Mercury's timeline into past, present and future. She first appeared in the Season of Dawn.

Niruul is the first boss in the rotating boss lineup of The Sundial. She traps Guardians in Void bubbles that kill them unless the bubble is broken, and at one third health she summons Psion Commanders who shield her until they are killed.