Haha. Maybe you could split the player roles, with 1-2 being normal and 1-2 being cults of elder gods. Give the normal players an extra figure "investigator". Give the elder god players "cultists" and "high priests". Have the elder gods build covens and temples instead of towns and cities. Give either side independent placement rules (so a coven or temple could be built on a city or town). Let the elder gods be able to subvert towns and cities (leaching their resources), and let the normal players erase covens and seal temples.