In 1975 TSR published D&D Supplement II: Blackmoor. It included something the world had never seen before. A published RPG scenario. This was the Temple of the Frog. At the time TSR didn't really believe there was much money to be made in publishing adventures and allowed other companies like Wee Warriors and the Judges Guild to publish adventures instead. The first published adventure however was the Temple of the Frog.
The Temple of the Frog was also the introduction of D&D's first real arch villain: "St. Stephen". Played by Stephen Rocheford, Rocheford and Arneson worked together to create this character as a humanoid alien with ties to extra terrestrial forces and technnology. St. Stephen had mutated frogs and other swamp creatures into servants who worshipped the alien as a god and protected his temple. The inclusion of advanced technology would also provide clues to another adventure location to be explored later
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