Agatha's mask was a plain white stage mask with a simple cord to hold it in place.
When worn, the mask bestowed on the wearer the illusory appearance of another race or monster. This effect only worked as long as the mask was worn and only effective to the naked eye; any magical scrutiny would reveal the true identity of the wearer.
For a long time, the mask was in the possession of the banshee, Agatha. In 1356 DR, Drizzt Do'Urden needed a way to enter the city of Calimshan without anyone knowing of his dark elf heritage. He and his barbarian friend, Wulfgar, acquired the mask without killing the banshee, as requested by the nearby villagers of Conyberry.
In 1357 DR, Artemis Entreri took possession of the mask from the halfling. While seeking a rematch with Drizzt, Entreri transformed himself into Regis on a visit to Mithral Hall. In the end, Entreri was left critically injured and hanging from a cliff, and Regis stole the mask back, as well as other magical possessions of Entreri.
Later in the year, Regis offered Drizzt the mask to help him on his journey to Menzoberranzan, but Drizzt turned down the offer. Later, Catti-brie took the mask to aid her in pursuing Drizzt, by disguising herself as a drow female. She lost control over the mask and it fell into Jarlaxle's hands, but she eventually returned from the Underdark with the mask.
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- R.A. Salvatore (February 2001). The Icewind Dale Trilogy Collector's Edition. (Wizards of the Coast), p. 754. ISBN 978-0786918119.
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- R.A. Salvatore (January 1990). The Halfling's Gem. (TSR, Inc), pp. 42–46. ISBN 0-88038-901-X.
- R.A. Salvatore (November 2005). The Legacy (reissued). (Wizards of the Coast). ISBN 0-7869-3984-2.
- R.A. Salvatore (July 2006). Starless Night. (Wizards of the Coast). ISBN 0-7869-1606-0.
- R.A. Salvatore (July 2007). Road of the Patriarch (Mass Market Paperback). (Wizards of the Coast). ISBN 978-0-7869-4277-0.