An Urban Sourcebook for Old-School Gaming
From the introduction:
The Storm Wolf, it is said, once challenged Astarte and Shamash to seize the people of the land. The Storm Wolf was defeated, and his people saved, but the Wolf declared that in time, the gods would fade and not be able to stop him. He would come back, and his faithful would grant him a place in the world, where he would devour their souls and bring the Great Storm of Blood. It is said that three witches worship the Storm Wolf, and that each has a secret cult of chaos in the city. They seek to bring the Storm Wolf into this world, to cleanse the land of the Empire, to cleanse the land of the works of men, and to make the world free again for the wild, for magic, and for chaos.
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Estarion is a setting for urban adventure in an old-school game such as Basic/Expert D&D, Labyrinth Lord, Swords and Wizardry, or Lamentations of the Flame Princess. However, the minimalistic presentation of the rules in this supplement can be used to adapt this game to any version of D&D or a d20 fantasy game or, with a little work, to other systems.