2002 · ソースブック（プレイを拡張するルール／オプション）

Rulers of the Sky

This fantasy sourcebook introduces the basics of adventures in cloud realms, where sky ships, flying castles, cloud cities, and airborne monsters fill the skies. It presents three new races—sky elves, arachial, and avians—along with two aerial prestige classes and guidance for using core classes in the air. The book adds aerial feats, expanded rules for combat above the ground, and guidelines for building and operating sky ships. It also includes an overview of the sky realms and eight monsters native to the clouds, and can be used independently or alongside other volumes in the series.