She drew him around the back of the tent. 'Look!' Irisis threw out her arm.

The shapes were unmistakable now. 'Air-floaters!' said Flydd. 'Twelve of them, and coming fast. So that's what the Council was up to.'

'Any reinforcement is welcome,' said Tham, pushing between them, 'though a dozen air-floaters can do precious little to help us now.'

'Let's wait and see,' said Flydd. 'Can you rustle up some breakfast, Irisis?'

In twenty minutes the air-floaters were overhead, flying in perfect formation, four wide and three high. They made a circle over the top of the battlefield and the fighting broke off as humans, Aachim and lyrinx stood by to see what their intentions were. Being so light, air-floaters could be driven by a distant field.

'They seem to be working to a plan,' said Irisis, wolfing down a gritty hunk of black bread. It was tasteless army fare, but she was too hungry to care.

The machines had maintained formation all the way around the circuit. 'It's almost …It's as if they're all controlled by one mind.' Flydd carved slivers off a distinctly green cheese and popped them into his mouth, two at a time. 'Though I know that's not possible.'

Flangers came up beside them, one hand resting on the hilt of his sheathed sword. 'They'd better look out!'

The two lyrinx sentries were now converging on the ranked air-floaters. One corkscrewed down to the left side, the other plummeted directly towards the top-right machine. The attack was co-ordinated so they would reach their targets at the same time. And air-floaters were vulnerable. One slash of a lyrinx's claws could tear the gasbag right open. Moreover, an attack from directly above was difficult to defend against.

The air-floaters shifted slightly out of line. Just before the higher lyrinx reached its target there came a flash that lit up the creature. Its wings folded up and it fell out of the air. Rotating slowly, it disappeared behind a boulder-topped hill. 'What was that?' said Irisis. 'I don't know,' the scrutator replied.

The corkscrewing lynnx beat its great wings, coming out of the dive right beside the gasbag of the air-floater. It gave a measured slash but, before its claws could part the fabric, it too was hit by a flash of light. The lyrinx's wings churned, it somersaulted backwards and fell, upside down. Halfway to the ground it seemed to recover, flapped several times and almost broke its fall, but lost it and plunged into the bloody mud of the battlefield at a speed that must have pulverised every bone in its great body.

'I don't sense the Art,' said Flydd, puzzled. 'What are the scrutators up to?'

The battle had not resumed. The air-floaters pulled back into that perfect formation, now hanging motionless above the battlefield, their rotors turning just enough to counteract the gentle motion of the air.

'I wonder …?' said Flydd. 'Who on the Council has the boldness for this kind of venture, and the foresight to know that it would be needed?'

Irisis had a fair idea, but she would just wait and see. From the topmost middle air-floater, rods extended to either side, all the way to the neighbouring machines, which latched on. A roll of shimmering fabric fell, was caught as it passed in front of the middle row of machines, and again at the bottom.

'What on earth are they doing?' said Tham.

No one answered. The air-floaters moved ever so slightly this way and that, bending the rods and pulling the fabric into a gentle concavity. It took a long time, for the slightest change in the breeze tended to drift the machines apart, and much manoeuvring was required to get them aligned again.

'It's a mirror,' said Irisis. But what is it for?'

'They're not using the An at all' Flydd replied. They simply hit the flying lyrinx with a dazzling beam. Lyrinx have poorer eyesight than we do, and their eyes are sensitive to bright light. They only fight in the middle of the day if they have to. The beam disrupted the An they were using to keep aloft, and they were too close to the ground to recover.'

'They're moving,' said Flangers.

The twelve air-floaters wheeled in perfect formation. The sun flashed off the mirror, the beam lighting up a strip of ground some twenty spans long.

The beam crept across the battlefield, to play on a group of lyrinx attacking a line of soldiers. Irisis focussed on the scene with a spyglass. The lyrinx threw up their arms, trying to shield themselves from the boiling glare, then broke and ran, staggering from side to side. One bold soldier attacked from behind, felling his quarry with a sword thrust between the back plates, but the others escaped.

The beam stepped to another group of lyrinx, who broke like the first. As it tracked across the ground, the mud began to steam gently. The next detachment, some fifty lyrinx, resisted longer than the others, but within a minute they too had fled.

'With a lens, anyone can focus the sun's rays so as to set paper or cloth alight,' said Irisis, 'though I don't think that's their aim here.'

'The beam isn't tightly focussed,' said Flydd, putting down his spyglass, 'but it's enough to dazzle and confuse. And blind too, should you look directly at it.'

The general had a calculating look in his eye. 'Shall I order the counterattack, surr?'

'Wait,' said Flydd. 'If the mirror tears in the wind, or the lyrinx make a determined attack on it, we'll be more exposed than we are now.'

The enemy now attacked desperately, but the beam stopped each onslaught. Within an hour the lyrinx began to fall back en masse, whereupon the beam moved towards the ranks of enemy surrounding the walled perimeter of Snizort.

Suddenly half a dozen lyrinx took to the air, well apart, rising into the path of the air-floaters. This'll be interesting,' said Tham. "They'll never move the mirror quickly enough.'

The air-floaters did not attempt to. The first lyrinx to approach took many crossbow bolts to the head and chest. It tumbled over and over, wings cracking in the wind, before slamming into the ground down the slope behind the command tent. The second suffered a similar fate, for the air-floaters were packed with archers. The other lyrinx flapped away. In the air they were too vulnerable. The mirror beam continued its inexorable progress.

'Something's happening,' said Irisis in the early afternoon. She was watching enemy movements inside the southern wall of Snizort. Lyrinx were running backwards and forwards through the drifting smoke. 'Looks like they're sending out reinforcements.'

'I don't think so,' said the scrutator.

Flangers said quietly, 'They're carrying boxes and bags.'

'Where's my spyglass?' Flydd demanded.

'You left it by the tent,' Irisis replied, passing him her glass. He focussed it and said, 'You've got good eyes, soldier.’

'That's why I was chosen as shooter.'

'What are they doing?' Irisis and Tham asked together.

'A group of .., perhaps one hundred have formed up behind the southern wall,' said Flydd. 'They've all got big packs on, which is unusual, and they're carrying what appear to be boxes, or cases. Or coffins!'

'The same thing happened yesterday morning,' said a sentry standing nearby. 'Even before the node exploded their fliers were heading south-west, carrying huge packages.'

'Is that so?' said Flydd. 'How odd.'

"The tar's burning underground,' said Irisis, 'and it would be the very devil to put out. They'd have to abandon Snizort, whatever the result of the battle.'

'I wonder if those cases contain flesh-formed creatures?' Flydd gave Irisis a keen glance. 'If we could only …'

'I hope I'm wrong about what you're thinking' said Irisis.

'Regretfully,' said Flydd, 'you're not. They're weapons we don't know how to deal with, but if we had one or two little ones to study, we might be able to find a defence against them.'