The Luminous Order isn't the only powerful group working behind the scenes in the Valley of Obelisks. A group of ambitious schemers - wizards mostly - exists solely to accumulate more power for its members. This faction is the Ebon Cabal, based in a fortress called the Black Tower.
The Ebon Cabal isn't an evil organization, though it probably has a few evil members within its ranks. It's definitely "neutral ambitious," however, and its members have few scruples about seeking and taking what they want. Over the course of the adventure, you might encounter the Ebon Cabal and become affiliated with the group. From time to time after you become affiliated with the group, I will tell you when your affiliation score within the Ebon Cabal has increased. As your affiliation score rises, you be come entitled to the following rewards.