Avatar Wars: Bane by Johndowson

Bane (also known as the Black Hand and the Black Lord), is the god of hatred, fear, and tyranny and one of the main evil gods in the Forgotten Realms.

Bane is a Lawful Evil Greater Power whose symbol is green rays squeezed forth from a black fist, and whose divine realm is the Black Bastion in the Acheront.
The Black Lord prefers to keep to the shadows, allowing his servants to carry out his intricate plans. He has no tolerance for failure and seldom thinks twice about submitting even a loyal servant to rigorous tortures to ensure complete obedience to his demanding, regimented doctrine.
He was never seen, although there are tales of a freezing black-taloned hand and eyes of blazing fire. With the rise of the Zhentarim network, the church of Bane began to gain power at around 800 DR, his influence spread to Voonlar, Mulmaster, Hillsfar, eventually covered the Realms. His largest temples are the Black Lord’s Altar in Mulmaster and  the temple complex in Zhentil Keep.

Together with Myrkul, he steals the Tablets of Fate from Helm. This act causes the wrath of Lord Ao and the exile of the gods on Toril.