The Riftwar Saga

Feist influenced her love of immersive secondary worlds, character-driven stories, and long fantasy series.

This is Feist's most significant and legally/historically acknowledged source. Feist has explicitly stated that the alien world of Kelewan, the Tsurani Empire, the absence of horses and metals, the insectoid Cho'ja race, and the pantheon of 20 major and 20 minor gods were all imported directly from Barker's setting. Feist initially wrote Magician without realizing his college tabletop gaming group had lifted these concepts straight from Barker's published RPG world. Once discovered, he formally acknowledged Barker's profound influence on the lore.