The Breaker Chains:

The owner of this wonder may select one of their vassals at the start of each age, or via a DC 30 mech-rp. This vassal cannot lose compliance from vassal actions, cannot disobey vassal actions, and automatically grants their overlord one of each of their resources that they produce. This may not be a player nation. Additionally, the owner of this wonder increases their admin and vassal slots by 1.