Waterdeep:Zhentarim

The Zhentarim, also called the Black Network, is a shadowy organization that trades mercenaries and goods (including contraband and slaves) all over Faerûn. The branch of Zhentarim in Waterdeep are called the Doom Raiders, and were formerly a group of adventurers who specialized in looting lich lairs.

An initiate to the Black Network is a Fang. At rank 3 they become a Wolf. At rank 10 they become a Viper. At rank 25 they become an Ardragon. At rank 50 they become a Dread Lord.