The Black Queen 

Very little conclusive information has been recovered about the person of interest called the Black Queen. She claims the given name "Alison Chao", the name of the daughter of researcher Dr. ██████ Gears and ██████ ███ Chao before Gears' recruitment by the Foundation.

The Black Queen possesses unusual knowledge of Foundation structure and activities, and contained anomalies. The reason for this unusual knowledge has yet to be conclusively identified, but it appears to be gained partially through anomalous means (including the possibility of extra-universal information sources). She has repeatedly been able to breach Foundation security utilizing this information, in addition to classified anomalous means.

Conflicting reports exist of the Black Queen's activities and motivations (likely due to multiple individuals or deliberate counter-intelligence). Initial reports characterize her as malevolent, murderous, and destructive. Other reports characterize her as neutral or benevolent. All intelligence indicates her hostility towards the Foundation.

There are reports of the Black Queen's involvement with most major Groups of Interest known to the Foundation, along with several world governments. Unverified sources claim that she is the same individual as L.S. of the Serpent's Hand, and that L.S. stands for "Little Sister". The reason for this unusual close connection is possibly due to the Black Queen's use of the Wanderers' Library.

The Black Queen definitely has some ties to The Serpent's Hand

The Black Queen by Mad Dummy April 9, 2019