by the metal they wore. The beast's gurgling roar burst over them redoubled as the horses were only starting to gallop up from the creek. The dragon had crested the rise from which they had first seen it. That meant that it was covering at least three feet of ground to every two of theirs. Perennius had assumed that nothing as huge as the allosaurus could keep up a high rate of speed for more than a short spurt. The truth was a draining surprise.
Ursinus had been wrong. He and his two companions had not escaped because they outrode their pursuer. They had been saved by the sacrifice of the fourth member of their party. It was as brutally simple as that. And with the same horses burdened by men in full armor, there could be no question at all of how the present race would end unless the riders found a haven which their speed could not vouchsafe them.
Gaius charged over the rise, by now three lengths ahead of the agent. The younger man tried to wheel his horse to face the monster. Perennius, half-blind from sweat and frustration, almost rode into him. Gaius was drawing his spatha. 'Ride you idiot!' the agent screamed. He was aware that Gaius must be speaking also and that both of them were barely able to hear their own voices over the cry of the allosaurus.
Perennius' mount had checked no more than required to veer around its fellow. They were on a rolling pasture of brush and sheep-cropped grass. Four hundred feet ahead of them was the near rim of a sinkhole, the mouth of Typhon's Cavern. A quarter mile beyond, with the rose and saffron of its rocks standing out against the dusty vegetation above it, was the far rim of the gorge.
The great gap in the earth stretched half a mile to either side. The eastern end was blocked from sight by a range of knobby outcrops, while the road wound around the western end of the rim. There was a separate track worn more by sheep's hooves than human deliberation. It plunged straight toward the gorge's south rim. Perennius lashed his horse in that direction instead of trying to skirt the cavity. The agent had Sestius' description of the site to guide him. The horse was too wild with fear to know or care that it was being driven toward a gulf.
The situation was out of control. Perennius knew he did not even rule the horse he rode. The agent's input was tolerated because the animal was not consciously aware that it was being driven forward instead of to the left. The agent had hoped that they would be able to deal with the Guardians in scattered pickets along the way. If that did not occur, then he had intended to reconnoitre the gorge at leisure, seeking a path to its floor besides the one switching back and forth along the south wall. Sestius had claimed there was no other path because the lips of the cavity overhung the floor elsewhere around the edge. Perennius had still hoped that care and the long rope lashed to each man's saddle would provide access in secrecy.
Right at the moment, Perennius' greatest hope was that the allosaurus would not be able to turn sharply enough when it blundered through the screening brush and confronted the sinkhole. The agent was quite certain that his own mount would plunge over the side. And Perennius was more than doubtful that he would be able to leap clear himself.
A figure rose from the cover of a ragged succulent. It wore a hooded cloak of blue so dark as to be black. Though the figure was little more than a shadow in a blur of sweat and dust to Perennius, the object it held and aimed glittered.
The world went red. Perennius' skin had crawled with
prickly heat. Now his whole body contracted with what its surface told it was a bath of ice. The agent's ears rang at a frequency high enough to be a perception rather than a sound. The ringing filled his head so completely that even the call of the dragon only strides away was swept into nothingness. All over Perennius' body, hair sprang up against his clothing with a violence that moved the iron-sheathed leather.
The agent was not shot off his mount. The horse, goaded by the crash and glare above it, hurled itself in an insane caracol. Even if Perennius had been fully aware, he was not horseman enough to have kept his seat amid that fury. Battered, his senses stunned by the ride and the discharge that turned him into a momentary flare, the agent sailed off when his mount shifted from beneath him. Perennius was unwitting of the fact until he hit the ground in a spray of dust and clangor.
The air stank of ozone and charred leather. The thongs that held the mask to the back of Perennius' helmet burned through when the mask took the point of the Guardian's blast. A rosette was seared across the silver facing. At the tips of the rosette, the brass back-piece and the iron gorget still shimmered as they cooled. Perennius' eyelashes had been burned away. At the moment, the agent was not sure that he was alive at all. His vision had tumbled dizzyingly from the mask's near blindness, through a red flare that was a result of direct nerve stimulation rather than sight, to the unmasked dazzle of a bright Cilician day. Nothing quite registered yet in his mind.
Gaius leaped his horse over Perennius' prostrate body. The beast was a white-bellied blur above the fallen man as the Guardian fired again. The air sizzled with the corona enfolding the young rider. His out-thrust sword roared with the cascade of sparks pouring from its point and double edges. Gaius lost neither his seat nor control of his mount. The horse gathered itself and sprang again as its rider's heels demanded. The Guardian made a high, keening sound nothing like the syllables which had come from the vocalizer of the thing in Rome.
The tip of Gaius' spatha split the cowled head as the horseman charged on by.
Reflex raised Perennius to join the battle his intellect was still too disoriented to comprehend. As the agent's shoulders lifted from the ground, the long-taloned leg of the striding allosaurus brushed him aside. Gaius' mount was skidding over the edge of the chasm. The monster's jaws slammed so close behind the horse that a fluff of long tail-hairs scattered from the edge of the carnivore's jaws. Dust, gravel, and the dragon followed the young Illyrian over the side.
Perennius wore over eighty pounds of armor and equipment. His thigh wound pinched him even at rest. The agent had been enervated by fear and the ride, then stunned by the shot he had taken and his fall. When he saw Gaius ride into the gorge with the dragon following, Perennius rolled to his feet. There is a limit to how long a man can live on his nerves. Aulus Perennius would reach that limit when he died on his feet.
The rim of the sinkhole had been undercut by the hungry ground waters. One of the earth-slips to which Cilicia is prone had shaken down much of the south wall into a jumble on the chasm's floor. The slope that resulted was steep, but at least it had some outward batter. Perennius ran to the edge without pausing for the tentacled thing that sprawled in his path. The edge of Gaius' sword had volatized with the energy it had sprayed back into the atmosphere. The weapon struck the Guardian as a blunt, glowing bar. It had the weight of a horse and armored rider behind it. The creature's conical head was not sheared but caved in. Shards of gray chitin were trapped in a magenta gelatine.
There were three more Guardians toiling up the trail toward the rim. They wore no masks or disguises, only their gray exoskeletons and a shimmering array of tools. The alarm that summoned them had been a little too late. It was unlikely that they were prepared for what came sliding down the slope toward them.
The trail itself slanted broadly to the right for several hundred feet before it cut back in the other direction. Gaius, whooping and still astride his horse, ignored the trail. He blasted gravel straight downslope toward the pair of Guardians a level below him. The gradient was
one to one, too steep for real control given the gallop that had taken man and mount onto it. It was not quite abrupt enough to make the descent a fall rather than a ride.
Horse and horseman bathed in a roaring dazzle. The Guardians had neither the desire nor the ability to direct their bolts at the man alone as their shattered fellow had done on the chasm's edge. The mane and tail of the horse flared out and burned. The powerful neck and shoulders withered as if they were at the core of a furnace. Shattered bone ends protruded from the carcase which was otherwise charred too black and dense to be seen as from an animal. It plummeted between the two leading Guardians, taking brush and a hail of limestone with it as it rolled toward the chasm's floor.
Gaius' long iron shirt flashed brighter and whiter than the sun in the instant the alien bolts gnashed at it. The spatha folded back on itself as if its blade were wax and not steel. Gaius flew forward, separating from the horse whose forequarters had been devoured beneath him. His armor glowed red and then red on black as air quenched the thousands of spot-welded wires which comprised the mail. Stiff as a statue and surely as unknowing, Gaius skidded until he hit a trio of mulberry trees, eighty feet below the rim.
No one, not even Perennius, was watching Gaius. The dragon was on top of the leading pair of Guardians.
For something that weighed as much as a yoke of oxen, the beast had incredible agility. It could not avoid the abrupt descent, but even as inertia carried its leading right foot over the side, its tail was swinging around. That long, cartilage-stiffened member was the lever by which the allosaurus pivoted its mass. As the beast slid into the chasm, it was already twisting broadside, cat-quick, to scrape itself to a halt in the shortest possible time. The allosaurus was not intelligent, but its nervous system housed bundles of reflexes as finely honed as ever an
