City State of the Invincible Overlord

City State of the Invincible Overlord was the first published fantasy role-playing game city setting, designed for use with Dungeons & Dragons (D&D), and officially approved for use with D&D from 1976 through 1983. It was published by Judges Guild and later under license by Necromancer Games.

City State of the Invincible Overlord was designed by Bob Bledsaw with the assistance of Bill Owen, and was inspired by Bledsaw's own Dungeons & Dragons campaign.City State of the Invincible Overlord was first released at Gen Con IX in August 1976.

City State of the Invincible Overlord launched Judges Guild as a company, and was the centerpiece of its Wilderlands of High Fantasy campaign setting, the first licensed and published Dungeons & Dragons campaign setting.

The City State of the Invincible Overlord setting itself was a single city designed to be both as a base for campaigning, as well as a seed for city-based adventures. A second product, Wraith Overlord, explored the city's subterranean cellars, sewers and catacombs.

The City State of the Invincible Overlord setting was used as a home-base for characters created by Judges Guild in other products. Attention was also paid to synchronising the setting with broader adventure possibilities: a northern Dwarven fortress city Thunderhold with an associated "dungeon" area; and a series of four modules written to explore areas adjacent to the route from the City State of the Invincible Overlord setting to Thunderhold, as well as a fifth which was to introduce a "witch" NPC character class.

The City-State has gone through several editions:

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