Duelist's Handbook (2nd edition) (2000)

From the back of the book:

The Duelist's Handbook brings Heavy Gear players into the ritualized and violent world of mechanized dueling. The guardians of regimental honor, the stars of professional sports teams or the vicious gladiators of the underground, Duelists exemplify all the best and worst qualities of the Heavy Gear world. The Handbook examines the duties and lives of the military, professional and underground duelists, and features new Gear and Mount models, dueling weapons, Perks and detailed rules for small scale tactical combat. Several prominent Duelists are also profiled, and details are provided on the Badlands city-state of Khayr ad-Din and its army – an ideal roleplaying setting for Duelists.