The Nameless

The Nameless was a female individual, supposedly a cultist of Vecna.

History
In 812 PD, the individual known as the Nameless betrayed the Remnants by stealing secret knowledge from Vecna and fleeing to Gatshadow Mountain in search of the spirit of Acek Orattim, a deceased priest of Tharizdun. There, she breached the lower gates of Gatshadow and became the new Herald of Oblivion, drawing the attention of the Remnants she betrayed as well as from the Arcana Pansophical.

Trivia
Critical Role: Tal'Dorei Campaign Setting offers the Nameless's flight to Gatshadow as an adventure hook was set "one year" after the fall of the Chroma Conclave, the final member of whom died on 12 Misuthar 811 PD. Exactly one year after that date (according to Vincent Clor), Vox Machina fought Vecna and his top lieutenants, and the next day Vecna completed the Ritual of Seeding and ascended to godhood.