Thomas's Forgotten Realms
The Shadow Lord
Mask is a loner god, most often associated with thieves or those of otherwise ill-repute. He is a Chaotic Neutral Intermediate deity whose portfolio includes shadows, thievery and thieves; although it previously also included intrigue. Mask’s symbol is a black velvet mask tinged with red. Mask is known for his constant scheming, cool head, and oft reserved biting comments.
During the Time of Troubles Mask took the shape of a powerful blade called Godsbane. He would eventually come to be wielded by the then-mortal Cyric. In the years following the Time of Troubles, Mask attempted to kill Cyric, but his plot failed and Cyric ascended as the divine god of intrigue.
In 1374 DR Mask relinquished his divinity and his life over to Shar to repay a millennia old debt to the goddess, who was revealed to be his “mother” as well as the person he served as a herald. Just before his death, Shar revealed Mask’s true name as Lessinor, though its origin (either as a mortal name or birth name) was not explained. A portion of Mask’s divinity was stolen and absorbed by other parties during this process.
There were several hints that Mask would return, either in person or via a successor who would take his place in the pantheon. This was proven to be true when another of the Shadowlord’s plans resulted in Mask’s divinity being gathered back into a single being, although some believe parts of his essence are scattered throughout the realms.