They continued crawling up the side of the valley, thence onto a fluted ridge of sharp rock. The sky had clouded over but now the moon came out momentarily and Irisis, beside Nish, caught her breath. The sudden brightness lit up the paved parade ground and mooring field which extended from the vertical slash of the thousand-span-high precipice that fell into the sunken lands of the Desolation Sink, all the way, as flat as a table, to the front wall of Nennifer. Two air-dreadnoughts were moored in the central part of the parade ground, one not far from this end, the other midway.

Nennifer’s monumental bulk reared up before them, the biggest building in the world and one of the most brutal in its sheer functional ugliness. It made no concession to beauty, harmony, proportion or setting: in a world devoted to war, nothing mattered but the power of those who told the world how to fight and die. Behind Nennifer, mountains black and bare rose up to pierce the glowing sky.

They were no more than five hundred spans from the front of the building. From here they would be exposed every step of the way, and within range of the great javelards and catapults mounted on the walls. If the sentries saw them, they would be shot without warning.

‘Where’s the amplimet, Malien?’ said Flydd.

‘Somewhere in the middle of the building,’ she replied. ‘I can’t tell more from here. The third floor, or perhaps the fourth. No closer, please.’ She choked.

‘What’s the matter?’ said Nish.

‘Something is very wrong. We must turn back.’

‘We have to go on,’ grated Flydd.

‘No further. I’m begging you.’ Malien’s face was stark in the moonlight. ‘Take another step and the mission will fail.’

‘If we turn back, we’ve already failed. Neither of you have the strength for another attempt.’

Yggur raised his head, which was nodding like a puppet’s. ‘What’s that?’ he whispered, looking at a small stone structure a couple of hundred spans ahead and to their left, not far from the edge of the precipice.

‘It’s a shed where they keep the mooring cables for the air-dreadnoughts,’ said Klarm.

‘Will anyone be there now?’

‘No reason why there should be.’

‘We’ll do it in the lee of the shed,’ said Flydd, ‘if we can’t get inside.’

They went on their bellies across the ice-glazed paving stones, and every wriggle of the way Nish expected to feel the pulverising impact of a javelard. He could make out guards moving on the upper walls. Surely Flydd’s meagre illusion couldn’t conceal them from such an unceasing watch?

The shed was built of flat slabs of gneiss laid in courses like long thin bricks, the mortar deeply raked so that the joints were half a fist deep and wide. The door proved to be locked so they took shelter against the end wall, whose shadow provided partial screening while allowing them to see the front of Nennifer.

‘Keep still,’ whispered Flydd. ‘I’ll have to release the illusion now, and the guards never fail in their alertness at Nennifer.’

‘They fail at times,’ amended Klarm, ‘but then they die horribly, as an example to their fellows. And rightly so.’

Nish gave him a shocked glance.

‘A guard’s duty is to guard,’ Klarm elaborated, ‘and all may rest on it.’

They put their backs to the rough stones while Yggur and Malien did their best to overcome their aftersickness, then made ready for the final attempt.

The night grew wilder. The wind, howling around the angles of the shed, rasped at exposed skin with abrasive particles of ice. The last of the cloud blew away and the moon appeared, brilliant in the thin mountain air. Then, as they watched, a pair of rings grew around it, the spectral colours little more than shades of grey.

‘Two rings around the moon,’ said Klarm. ‘Not a good omen.’

‘It’s better than a moonbow,’ grunted Flydd.

‘Not much, and we may see one as it rises.’

‘Let’s get on with it,’ said Yggur. ‘Malien?’ The moonlight gave her face a bluish cast.

‘Are you all right?’ said Nish.

‘Just thinking,’ Malien said, ‘of all the ways it could go wrong.’

As soon as she and Yggur began, the crystal’s inanimate fury hit Nish like a blow to the stomach. For a minute he struggled to draw breath and, when it passed, his belly throbbed. They had no idea what they were dealing with.

Yggur and Malien were sitting side by side, she sagging in her bubble, he propped against the wall with his face enveloped in pale filaments. The bubble was dull this time, else it would have been visible in the shadows.

‘Ready?’ Yggur’s jaw moved oddly, as if the threads were working it like a puppet.

Malien’s affirmation was just a distant echo.

‘The amplimet is hungry for power,’ said Flydd. ‘All you have to do is melt the ice wards surrounding it.’

‘If we alert Fusshte’s mancers,’ said Malien, ‘they’ll shut it in a shielded box and we won’t be able to reach it.’

‘Then flood it with power directly. That’ll warm it up. But whatever you’re going to do, do it now. The guards patrol this area and they could come by at any time.’

Nish heard Malien’s inrushing breath, the bubble darkened and she let out a pained grunt.

‘Withdraw!’ gasped Yggur, but there was no reply. The bubble had gone black and nothing could be seen inside.

‘Come back, Malien, wherever you are,’ Yggur choked. He tried to get up and fell forward, right into the moonlight.

Everyone went still, knowing that the guards on the wall must have seen the movement. All at once Irisis leapt up, grabbed Yggur’s legs and began to drag him back.

A klaxon sounded from one of the corner guard towers. It was answered by half a dozen others, then a javelard spear screamed off the paving stone where Yggur’s head had been a moment before. Nish grabbed a leg and heaved, heedless that Yggur’s face was being dragged across the ground.

Another spear dug a span-long groove in the stone before Nish and Irisis got the big man around the corner.

‘And now we’re dead,’ Nish said.

‘Like hell!’ Irisis said savagely. ‘Run, while we still can. Maybe we can attack from the rear of Nennifer.’

‘We can’t carry Yggur and Malien,’ said Flydd.

‘Then leave them behind!’ she snapped. ‘I thought you were a ruthless scrutator, not a puling defeatist without any balls.’

Nish froze, holding his breath. Flydd gave a strangled gasp of outrage, but then a hail of heavy spears slammed into the far wall, flinging shattered rock everywhere.

‘Come on!’ she hissed. ‘The soldiers will be on their way.’

‘It’s too late –’

Malien’s sphere expanded then shrank again as if she was breathing it in and out. Its surface roiled, solidified like the shell of a nut then turned transparent again. They could now see her inside, working desperately with her hands as if trying to contain something too hot or bright to touch.

A catapult ball tore half the roof off the shed, showering them with broken tiles and splinters of wood. One of the soldiers, hit on the head, slumped sideways without a sound.

‘Another couple of those and there’ll be nothing to hide behind,’ said Flangers, flicking fragments of tile out of his crossbow. ‘They can pick us off without risking a man.’

‘The scrutators don’t care about risking a thousand men,’ said Klarm. ‘Now that the shock has worn off, they’ll want us alive.’

Malien doubled over, holding her midriff, but forced herself upright and extended her fists in front of her. The shell burst into fragments that fizzed to nothingness in the air. She brought her fists together with a spray of light and stood swaying on her feet for a moment before sliding into a crumpled heap.

‘The amplimet was waiting,’ she said faintly. ‘I couldn’t contain it.’

In the distance something went crack, like a long, brittle crystal being snapped in two.

‘What happened?’ asked Flydd.