Amaya Nightwind, also known as the Nightwind Executrix, was a Knight of the Aeonguard.
She was the wielder of the twin void relics, Zero Wing and Avarice Eye.
According to Sister Basilika in Recollector Log No. 13 - Effigy of a Rotten Girl, Amaya is the deadliest assassin of the Knights of the Aeonguard.
