From publisher blurb:
THEY STRIKE WITHOUT WARNING!
Forced to raid to survive, the crystal raiders strike from the skies in their magnificent wooden airships, taking what they need and cutting down any who stand in their way. Known for the unique crystal weapons that gave them their Name, the highland trolls find beauty in the harsh environment of the mountains, which also inspires their rich, complex culture of honor, duty and loyalty. Made up on many individual clans and moots, only the power of their fierce hatred of the Therans can force them to cooperate with each other. Other nations know that Barsaive may never escape the threat of the Theran Empire without help from the crystal raiders, but the first step is finding a way to gain and hold their trust -- a task that may require many to die before it is accomplished.
Crystal Raiders of Barsaive offers Earthdawn gamemasters and players an indepth look at the troll raider clans that sail Barsaive's skies and prey on the lowlands. This book describes the nine most powerful trollmoots in Barsaive, including their histories, goals and significant members. Crystal Raiders of Barsaive also includes new rules for airship combat, descriptions and statistics for several new airships and airship weapons, and numerous adventure ideas to help gamemasters incorporate the crystal raiders into their Earthdawn adventures and campaigns.