The ground shook with the thunder of hooves. Ten thousand horses streamed across the valley in a brilliant crescent, the morning sun glinting off the spiked helmets of their riders. Even from this distance Erhi could see that the Khwarezmid horses were big stallions, at least two hands higher than Sabar. Their riders let out a war cry as they galloped across the valley, a shrill ululation that curdled Erhi's blood. Sensing her mistress's nervousness, Sabar turned one way, then the other, rubbing her flank against a neighbouring horse.

"It'll be alright boy, don't you worry. Jebe knows what he's about" said her neighbour, a grizzled old warrior who had thick scar running across his neck.

Erhi couldn't take her eyes off the tips of the Khwarezmid lances. They appeared as if they were a single sea of steel, a great menacing wave set to crash down on the Mongol army. There was no way that Erhi could make it past the reach of those lances with her scimitar and even if she could, their armour was thick and finely plated, almost impossible to dent. This wasn't a hunt or a fight in the snow, this was war. What was she even doing here? She should be back at home where she belonged, with her mother and the other women of the court. She felt panic rise up her gullet and spread its cold hand across her chest. Her breathing became short and sharp and her cheeks flushed with colour.

"I pissed myself before my first battle, so by the smell of it you're already doing better than me" said the old warrior, letting out a rasping laugh.

Erhi couldn't help but smile. It was the sort of crude joke that usually annoyed her, but right now it's exactly what she needed to hear. Her panic faded and she began to breathe steadily. This is where she belonged, not at court with the other women, but here, with a mare under her legs, a quiver on her back and a blade at her side. Here, a new warrior fighting side by side with an old hand, nervous but alive, oh so very alive. She wasn't nameless, she was Erhi, and today was her day.

A horn blew out a single sharp note. That was their signal. The Khwarezmid cavalry had reached the mid-point of the valley, entering a low dip that occurred before the earth sloped upwards towards the Mongol position. The undulating ground broke the momentum of their charge and Erhi readied her bow. Their orders were to loose two shots, then turn tail and flee. She notched an arrow into place and drew back her bow, aiming high so that it would arc down into the middle of the cavalry where it was more likely to find a target. The lead riders were already charging out of the dip and up the slope towards her. She could make out the red plumes on their helmets, which appeared as brilliant streaks of colour amidst a blur of steel.

A whooshing sound filled the air as the Mongols loosened their bows. Erhi didn't look to see what damage she had done, as she was already busy drawing the second arrow from her quiver. The sound of arrows in flight gave way to shrieks of pain from man and animal. They had found their target. After Erhi loosened her second arrow she glanced down the slope. The low dip was littered with fallen horses and their riders. Bodies writhed and kicked in the mire, but she had little time for sympathy as the enemy was almost upon them, less than a hundred yards away.

The horn rang out for a second time, trilling rapidly to signal the retreat. Erhi slung her bow over her back and turned Sabar's reins. She followed the old warrior and spurred Sabar over the brow of the hill. The Khwarezmids let out a whoop of victory and she felt the hot breath of their pursuit upon her back. The Mongols cantered down the other side of the hill, not going so fast as to run out of reach, but instead staying tantalisingly close to draw the Khwarezmids onwards. As they reached a false flat, Erhi risked a look over her shoulder. The enemy was only a few strides away. Their lances bore down on her, straining to pierce Mongol flesh. Their eyes were narrowed with bloodlust and the extra height afforded to them by their horses meant that they towered over their quarry.

But Erhi was not concerned about the enemy riders, what she cared about, what every Mongol on the battlefield cared about, was the state of the Khwarezmid horses. With an expert eye she saw everything that she needed to know. Their mouths were flecked with white foam, their eyes were rolling back in their sockets and every sinew of their brilliant bodies was labouring at the end of endurance. The Khwarezmid horses were tired, worn out by the long charge up hill and the unexpected pursuit. They had them exactly where they wanted.

The horn rang out fora third and final time. The fleeing Mongols split into two groups, wheeling around in two large arcs, turning their pursuers in on themselves. Up on the brow of the hill a new Mongol cavalry division had appeared. They had been hiding in the forest, waiting for the perfect moment to emerge. At their head was Jebe, indistinguishable from the other Mongols except for a brilliant gold mask that covered his face. If death had a face, then this was it. He raised his hand, holding aloft his curved sword, then he charged down the hill, a streaking comet of carnage and gold. The Khwarezmids had gone from hunters to hunted in less than a minute. Boxed in from all side, their charge broke and they dithered. Their lances no longer seemed so long, nor their armour so thick. Their horses seemed smaller and less imposing, and their brilliant red plumes looked like markers of death rather than victory. Erhi's moment had come. She drew her scimitar and charged.