strangled squeak and abruptly fell onto his side, thrashing and clutching at his left shoulder. Two others simply collapsed, dead or unconscious.
Rushing water abruptly spread over the ground beneath the walls, rolling across it like a vast mirror that reflected the deadly glory of the ongoing aerial battle.
They waited, while the engineers kept up the effort of redirecting the little river. Men collapsed every few moments. Lord Riva's face became strained, with blotches of color on his pale cheeks. The water rose.
Then one of the vordbulks let out a higher-pitched bellow as one of its feet slid out from beneath it, sliding on the smooth clay surface made slippery by water and by the dust and grains of dirt churned up by the passing of so many mantis feet. It listed far to one side, like a ship wallowing between swells, but then slowly, slowly righted itself. A moment later, it took another step and resumed its advance
"Close!" bellowed Bernard back toward Riva over his shoulder. "Can you give them a shake?"
"Aye!" Riva panted, his jaw set. Then he closed his eyes again, speaking to the engineers, and suddenly the earth itself groaned. It jerked and quivered once. Then it lurched abruptly to one side, and Amara staggered against Doroga, who caught her and prevented her from falling.
Out on the field, two more vordbulks, no more than two hundred yards from the walls, screamed and slipped, falling awkwardly. They pitched over toward their sides in motions that were rendered slow-looking by sheer scale. It took them what seemed like seconds to fall, letting out bone-shaking basso calls of distress as they did. They hit the ground hard, driven by their own vast weight, sending tons of water and mud flying into the air with the impact. Dozens, if not hundreds, of vord were crushed beneath each of the monstrous creatures, whose weight was sufficient to leave a deep impression even in the baked clay. They thrashed, their limbs crushing more vord, and moaned out low calls that made the surface of the shallow water around them quiver.
"Good enough," Bernard said. "Good enough. It'll have to be." He looked at Giraldi, suddenly sweating. "Centurion, the stone."
Giraldi reached into his pouch and retrieved a smooth, oblong stone of the same color as the wall. He passed it to Bernard, who placed it upon the ground, and said, "Prepare to sound retreat."
The trumpeter looked nervously out at the field and licked his lips.
Bernard took a deep breath, then drove the heel of his boot down onto the stone, shattering it.
A pulse of cold wind seemed to flow out from the broken stone, raising dust and smearing fresh blood into new streaks. Seconds after it did, one of the merlons, the large blocks of stone atop battlements, suddenly quivered and groaned, its form twisting into a new shape. What looked like a Phrygian sled dog seemed to come shuddering out of the block of stone as if digging its way from a snowbank.
It promptly turned, lunged forward, and crushed a vord warrior against the opposite merlon, splattering the mantis to shards of broken chitin and smears of green-brown blood.
All along the walls, the canine gargoyles came to life and began smashing into the vord with implacable ferocity - and once all of them were free of the merlons, the stone beneath that recently vacated place began to quiver and heave, and more gargoyles began to emerge.
"Sound retreat!" Bernard ordered.
The trumpet began sounding the signal, and the Legions moved back instantly, as if Bernard's voice had carried to each and every one of them. Amara joined her husband and the rest of the command staff as they turned to abandon the walls, while all around them more and more canine gargoyles tore their way free of the stone that made the wall and began killing vord with what looked like ferocious glee, their upcurved stone tails wagging.
The mules and their teams were already on the move, and as Amara reached the Valley floor again, she noticed - the ground was growing soft even on this side of the wall. Riva stayed where he was, gasping, both hands on the ground.
Amara rushed to Riva's side, and said, "Your Grace! We've got to go!"
"In a minute!" he panted. "Ground on this side of the wall is all loose earth. Watering it will slow them down even more."
"Your Grace," Amara said, "we do not have a minute." She turned to the engineers and snapped, "You men heard the