Warbreaker is a stand-alone fantasy novel by Brandon Sanderson

Brandon Sanderson

Brandon Sanderson is an American fantasy author. A Nebraska native, he currently resides in American Fork, Utah. He earned his Master's degree in Creative Writing in 2005 from Brigham Young University, where he was on the staff of Leading Edge, a semi-professional speculative fiction magazine...

, published in hardcover in June 2009 by Tor Books

Tor Books

Tor Books is one of two imprints of Tom Doherty Associates LLC, based in New York City. It is noted for its science fiction and fantasy titles. Tom Doherty Associates also publishes mainstream fiction, mystery, and occasional military history titles under its Forge imprint. The company was founded...

. Sanderson released several rewrites of this title under a Creative Commons

Creative Commons

Creative Commons is a non-profit organization headquartered in Mountain View, California, United States devoted to expanding the range of creative works available for others to build upon legally and to share. The organization has released several copyright-licenses known as Creative Commons...

 license, one chapter at a time. Older drafts of the various chapters are also available. The entire novel is available in digital format from Sanderson's website. Warbreaker has been well received by reviewers.
Warbreaker tells the story of two princesses, Vivenna and Siri.