The Voidsingers also have a unique unit, the Cultist. It has all of the Monument's base effects, and provides additional Faith and Great Works slots. Joining them unlocks the Old God Obelisk, which replaces the Monument. The Voidsingers follow a dark religion of ancient gods and sow chaos to control adversaries.
Members of the society can eventually build the Alchemical Society, a University replacement building that has all of the base University effects, plus extra Great Merchant points, Great Engineer points, increased Production, and Gold. They also grant bonus yields whenever a Great Person is earned. Ley Lines are a new map resource only Hermetic Order members can see, which gives major adjacency bonuses to all specialty districts. Their success comes from theories and inventions that other societies dismiss as mere fairy tales, such as Ley Lines.
You 'join' the Society simply by choosing to promote this new Governor, using one of your Governor titles (hence the free title you gain when discovering the first Society!) Once you go through this 'initiation' process, competing Governors from other Societies will disappear - you may not join more than one Society. A new Governor will appear in your Governor screen - a representative for the respective Society, which will be your liaison with them.
Note also that the first time you discover a Society (any Society), you will earn 1 Governor title. Once discovered, a Society will send you an invitation to join them. The chance for discovery is not always 100%, however - you may need to perform the necessary action several times in order to discover a society.
By dispersing a Barbarian Camp, you discover the Sanguine Pact.By visiting a Tribal Village you discover the Voidsingers.By discovering a Natural wonder, you discover the Hermetic Order.By sending an Envoy to a City-State (or earning one by meeting it first or fulfilling a quest), you discover the Owls of Minerva.This is achieved via a specific gameplay action, which is different for each society: To join a Society, the player has to 'discover' it first. The Secret Societies Game Mode introduces four new "societies" - secret organizations with unique abilities which players may use to their benefit. It requires either the Rise and Fall or the Gathering Storm expansion to play. Each society has its own perks for the members, including new resources, buildings, tile improvements, units and city projects. It includes four different Secret Societies that players can join, but once a society is chosen, its membership will last the entire game and cannot be changed. Secret Societies is the second game mode in Civilization VI, introduced in the Ethiopia Pack.