As Pe had observed, the left end of the infantry flank was open to attack. Normally, Batu would take advantage of some terrain feature to protect this vulnerable area, or at least he would cover it with a contingent of archers or cavalry. But Kwan's orders were clear, and the general was too good an officer to disobey. Even a bad plan was better than a broken plan, which was what they would have if Batu did not do as instructed.

Batu ran his eyes down the length of the line, studying the route he expected the enemy cavalry to follow. As the enemy charged, the pengs on the left flank would fall, leaving other men exposed. Batu would supply some covering fire with his archers, and his cavalry would mount a counterattack that might slow the charge for a few moments. Still, the Tuigan horsewarriors would smash the line, killing all thirty-five hundred infantrymen.

Batu considered the possibility of issuing an order he had never before given: retreat. If his troops fell back before the charging Tuigan, his army stood a better chance of remaining intact. The reprieve would be a short one, the general knew. As the line curled back on itself, his entire force would be trapped in the reeds along the riverbank.

"And then the slaughter would begin," Batu whispered to himself, picturing the rushing floodwaters red and choked with the bodies of his soldiers.

"Forgive me, General. I didn't hear your order," Pe said.

"It wasn't an order," Batu responded, still eyeing the rushes and the river. "I said, 'And then the slaughter would begin. …'" The general stopped, still picturing his army floating down the river-but this time, they were alive. "Unless we can walk on water."

Pe frowned. "Walk on water?"