The Advantage is Gone With trenches behind them and the doorway to the east ahead, victory seemed a matter of time, until the Easterners introduced their own technological terror: poison gas. The new weapon throws the Western Alliance's lines into chaos, causing the first major retreat since the war began. Behind the lines, new allies and new unrest increase the uncertainty as diplomacy and espionage threaten to open new fronts at the worst possible moment. Now Ky and Lucilla must race to come up with a counter for these new threats before all is lost.