'Whatever it takes. Velmeran, we have to hurry,' Dveyella said as she fastened down her helmet. Velmeran fastened down his own and hurried to join her at the edge of the shelf, looking out over the ancient city. It was an impressive sight, seen from above, filling the valley from rim to rim and extending far to the north. The sprawling structure was composed of a series of massive, featureless stone blocks joined by connecting halls and corridors, unbroken by doors, windows or visible vents. But the greatest part of the city lay below, carved deep into the heart of the mountains.
'Keep your helmet on and your systems to normal,' Dveyella warned. 'Life has been gone from this world for so long that the oxygen level is still a bit low. Too low to sustain us for what we have to do. Ready?'
'Of course.'
'Stay close, then,' she said, peering over the ledge to the ground below. 'And remember that this is real gravity, not the stuff you practiced in. You will fall faster.'
Dveyella casually hopped off the ledge, jumping out just far enough to keep well clear of the cliff face, although she took most of the twenty-meter fall straight down. She landed easily and quickly stepped out of the way, and Velmeran followed. As she had warned, he fell faster than he would have expected. But he was prepared and maintained his balance effortlessly. Dveyella waited until he indicated for her to go ahead.
They kept up a fairly good pace the rest of the way down the slope, running where they could and clearing the more difficult sections in short leaps. Since most of this ridge was composed of tumbled slabs and boulders of solid rock, a good deal of their descent was spent jumping from one massive stone to another. Velmeran was hard pressed to keep up the pace that Dveyella set with ease. But he did not complain, since he thought that he would improve quickly with practice.
The major worry that occupied his thoughts was of Keth and how they might get him back up this slope, especially that final cliff. The dark brown soil and large brown-gray stones were loose and bare of supportive vegetation, as if the entire ridge had just been thrown up by the excavations of some immense machine. Large sections of the crumbled talus were entirely too loose to climb (not in heavy armor) and could only be cleared by jumping. Rain would quickly turn the entire slope into a slick, flowing mass, so they had to be back before the storm moved in.
They reached the bottom of the slope in only a few short minutes, moving stealthfully the last few hundred meters. Fortunately there were enough large stones — apparently the eroded rejects from the building of the city — to keep them well hidden to within the last ten meters of the door. Then Dveyella went ahead to check out the entrance for surveillance equipment and automatic weapons, although she was confident that there were none. This was, after all, only a supply base, an immense warehouse, on a planet where no one but the military was allowed.
It did not take long for her to decide. She paced up and down before the four broad steps that led up to the deeply reset portal, glancing up at the massive blocks of stone framing it and peering into the deep shadows that hid the door. At last she shrugged and signaled for him to join her.
'Nothing?' Velmeran asked as he hurried up.
'Nothing fancy,' Dveyella replied. 'There might be a simple detector on the door itself, but there is nothing we can do about that. You get down behind these steps and shoot anything that moves when I open the door. Fortunately these sections swing out, not in.'
Velmeran drew his guns, one for each set of hands, and crouched down on the large flagstones at the base of the steps, directly in front of the right of the two massive portals. Dveyella took firm hold of the thick handle and jerked it back briskly, using its bulk to shield herself. Nothing stirred within, and Velmeran held his fire. His eyes, large for excellent light sensitivity, could detect no movement. Dveyella watched his response, then drew her own guns and peered cautiously within, first checking the inside walls where he could not see.
'Clear,' she said. Velmeran followed her inside, standing guard as she closed the door. 'Straight ahead now, until we come to the first major stairwell. Remember to shoot anything that moves; in this place, it will not be your friend. Remember also that the sentries have heavier guns and thicker armor than you do.'
They hurried on, moving cautiously from room to room. The main corridor leading in was bisected often by buildings of various shapes, most fairly large and yet only simple, featureless structures. It occurred to Velmeran that these were auxiliary warehouses, perhaps only temporary storage areas for goods arriving or departing overland from other cities, later to be carried down the stairs and ramps to the lower levels. The main warehouses were probably on the lower levels, along with the inhabited areas, where the temperature was even more constant year-round.
Velmeran quickly chased such stray thoughts from his mind. They had just entered a small, rectangular room where the main hall was intersected by two parallel corridors. Dveyella came to a sudden halt at the first of the two smaller passages.
'Sentry!'
Velmeran did not need to ask where, for he could see the machine ambling down the corridor to their left, a tall, heavily armored shell on four long legs. It was perhaps twenty-five meters away, and had already passed the doorways to two adjacent rooms. 'Can it see us?'
'I have always suspected that the things are blind to the rear,' Dveyella answered, making no effort to hide as she watched the machine. 'Nothing back there. They do have stereoscopic cameras in front, like most advanced automatons, as well as echo-location and infrared sensors. It would hear us talking, if not for our helmets.'
The sentry turned off to one side, into another chamber to its right. Velmeran had only a brief glimpse of the machine as it turned; it was considerably taller than himself, at least two meters, and the rounded, armored shell of its body was nearly as long. Dveyella watched until it disappeared, its long whip tail dragging under the top of the door.
'I have to see where the thing is going,' she said suddenly. 'It is headed in the same direction we have to go. Watch these passages for a moment.'
Hardly giving him time to protest, she hurried off after the sentry. She crept cautiously down the side corridor and slowly leaned forward to peer around the corner, her guns ready. Then, to Velmeran's consternation, she slipped around the edge of the doorway and disappeared. Suddenly finding himself quite alone, he recalled her instructions and quickly checked each of the remaining corridors, fearful of seeing another of the hulking white sentries ambling toward him.
His unease was based in part on the shadowy presence of the sentry he sensed almost subconsciously behind the wall to his back, or perhaps the presence of its small generator. Nor was it aware of him as it made its ceaseless rounds through the ancient corridors. As it passed the doorway it caught a glimpse of something in the adjacent room, and paused in midstride for a quick double take. For a long moment it stood, as if checking its memory in an attempt to recognize this intruder. Then it began to move again, bringing itself around to face its enemy. It lowered its head to bring its guns to bear and charged at the best speed it could manage.
Velmeran was, unfortunately, facing in the other direction at that moment. He turned to make a second check of the other corridors, only to find the sentry already charging at him. The two adversaries opened fire on each other at almost the same instant. The sentry was a poor shot, shuffling forward at a ponderous pace. Velmeran had better aim, but his own guns could not pierce the sentry's armor. A single bolt struck him in the chestplate early on, knocking him slightly off balance. He recovered quickly and returned fire, this time aiming at the machine's vulnerable points. An instant of concentrated fire destroyed the heavier turret over the sentry's shoulders, then the two lighter guns mounted to either side of its head.
Weaponless, the sentry charged on, intent upon crushing its prey against the wall. Velmeran fired a few more shots, then bolstered his guns in time to catch the automaton by its ruined head. The sentry was the heavier of the two, well over a ton, but Velmeran was the stronger. Holding tightly to its head, he swung the machine around as hard as he could. His hope was to throw it on its side and render it helpless. Pulling as hard as he could, he swung it around in three-fourths of a circle. Then its retractable neck snapped, and he was left holding its head.
As surprised as he was, Velmeran thought that was the end of it. But the sentry caught its balance and charged again, and he hardly had time to drop the lifeless head and catch it by the flarings that protected its neck. Slowly it pushed Velmeran back, forcibly sliding him across the stone blocks of the floor until he was braced against the wall. Velmeran began to consider a desperate plan, and leaped aside in the hope that the sentry would run head-on into the wall. He knew that he had to do something immediately, for his strength was fading quickly.
At that moment Dveyella slapped a heat charge against the back of the sentry's shell. A second later the
