Grave Covenant — Michael A. Stackpole

ONLY ONE WAY TO STOP THE CLANS

Possessing precious secret information that will lead them down the Exodus Road, the Inner Sphere Successor States can now meet the Clans on their own terms...and behind enemy lines. The Herculean task of amassing enough power means re-establishing the legendary Star League -- a union of the Successor States and their BattleMechs led by Victor Steiner-Davion. But with the deadly game of politics making the Successor Lords wary of alliance, and Victor's Machiavellian sister, Katrina Steiner, hatching more vicious plots to further her own agendas, the war against the Clans may only be a distraction from the real danger....