 It was later republished under license by Necromancer Games.Bob Bledsaw and Bill Owen founded Judges Guild in 1976 to sell subscriptions to gamemasters, but they needed a real product to get things going, so they began work on a large map inspired by Bledsaw's own "Dungeons & Dragons" campaign.They finished this first product, "City State of the Invincible Overlord", just in time for Gen Con IX (1976).