This book is intended for Game Masters and advanced players. It covers physical feats, combat, vehicles and technology, animals and monsters, world design, and Game Mastering. "Tool kit" chapters let you create new creatures (and even PC races), artifacts, character abilities, and entire game worlds. It also features a cross-world setting, Infinite Worlds, which you can use to create cross-genre campaigns ... develop alternate histories ... play modern characters in a fantasy world ... whatever you like! Book jacket.