As Serena Butler’s Jihad taught us, we must use any conceivable weapon to fight the enemies of humanity. But what if those foes are themselves misguided humans?

—PTOLEMY, Denali research journals

When he finished repairing the first of the superlative cymek walkers, Ptolemy felt the return of excitement, even optimism. As he became absorbed in studying the mechanical systems, he almost forgot the pain and disappointment of working alone. Without Dr. Elchan, Ptolemy’s work had become an obsession to restore order and fix something that had been broken. And he had to do it for the good of humanity.

The thoughtrode interfaces connecting the nerves to the armored limbs were extremely complex, and Ptolemy still had much to learn before he would be able to control a mechanical warrior form using neural impulses. On the plus side, the armored bodies were straightforward machines driven by engines, pistons, and cables, and they could be controlled using more traditional means. Ptolemy constructed a small cab slung under one of the crablike bodies. Sealed and pressurized, with hard-linked inputs to the machine controls, the cab was equipped with life-support systems that would allow Ptolemy to ride inside while he explored the murky, caustic landscape of Denali.

When he finished testing the systems, Ptolemy climbed through the hatch of the control cab, sealed himself inside, opened the valves on the air tanks, and powered up the systems. The great machine hummed, and the crablike body raised itself on bulky legs.

Even as he imagined being one of the neo-cymeks, he realized that Elchan would have scolded him for such hubris. Ptolemy’s whole life had been devoted to progress and the betterment of civilization, never to personal glory. Yet now, he knew that if he succeeded with what he had in mind, great fame and widespread admiration could very well be his. If he survived, and people understood.

The veteran researcher moved one of the six legs forward, followed by another, and then another. It was a complicated task to walk in the apparatus, not at all intuitive, and it amazed him that the cymeks had ever been able to operate their machine bodies so fluidly, and in such a wide range of configurations with legs and grappling arms, rolling treads, and even wings.

Anxious to practice with the modified machine, and to see what he might discover and salvage out on the hostile landscape, Ptolemy sealed off the lab hangar, depressurized it, and used a remote signal to open the bay doors. Greenish fumes roiled into the hangar module.

Peering through the plaz windows of his control cab, he set the jointed legs in motion. Delicately at first, and gradually with more confidence, he plodded out onto the boulder-strewn expanse among the Denali research modules. The veil of toxic clouds gave the surroundings a distorted, dreamlike appearance. The light glowing from the research modules was fuzzed by the mist.

Adjusting to the rolling, synchronized movement of three pairs of legs, Ptolemy crossed the flat landing field where shuttles dropped off supplies, and then he ventured beyond the vicinity of the research facility.

Years ago, while building this secret outpost at an old cymek base, technicians in environment suits had scouted a kilometer around the facility, but had done little actual exploring farther away. This facility’s mission was to conduct important research projects far from the prying eyes of the Butlerians; few of the scientists were interested in mapping an inhospitable world. Josef Venport certainly didn’t care about the scenery on Denali. Ptolemy, though, was focused on trying to locate any remnants of the old cymeks, technology that he might put to use.

As the machine body strode away from the fading lights of the lab domes, he activated his illuminators. Bright eyes stabbed cones of light into the swirling chlorine fumes. At the top of a low rise, he came upon a junkyard of cymek bodies, large mechanical forms strewn about like carrion on a battlefield. They had dropped in their tracks, like the bones of prehistoric beasts that had come to a special graveyard to die. For him, it was a treasure chest.

He halted the clumsy footsteps of the machine legs and stared in awe and delight, imagining all of those warrior forms functioning again, a resurrected army of them. Such a force could stand against any mob of Butlerians! Ptolemy realized he was grinning: If Manford Torondo came to destroy the Denali facility, he would find it defended by his greatest nightmares.

Even sprawled on the rocks and deactivated, the walker forms looked fearsome. Ptolemy recalled stories about the Titan Ajax, whose machine body had slaughtered entire populations that rebelled against him. Across the screen of his imagination, he envisioned cymek machines grabbing the superstitious Butlerians, the Swordmasters, anyone intent on mindless destruction.

Inside the sealed cab, he worked the controls and clumsily raised the front jointed leg of his walker, lifted a clawlike footpad, and closed it. In his mind, he pictured grasping the torso of Anari Idaho and crushing her. He imagined that Manford’s savages would throw themselves upon the walker bodies, crawling over them like lice, pummeling and smashing. But it would do the fanatics no good. These cymek walkers were far too powerful.

If he’d only had access to a mechanical body such as this earlier, he could have killed all the Butlerians who raided his research facility on Zenith … and even if he hadn’t gotten into the body in time to save the life of Elchan, he might have forced the legless Manford Torondo to watch the slaughter of Butlerians, just as the vile man had made Ptolemy witness the horrible death of his closest friend.

Now as he operated the external controls from the enclosed cab, he realized that his limbs and grasping hands were far too clumsy for a swift and fluid battle. He would need to find a direct neural interface so that he—and any other defenders of civilization—could operate the machines with the proper finesse.

He plodded past the cymek graveyard and went farther along the ridge to where the murky gases cleared. There he found collapsing structures, along with a hundred more armored walkers. Ptolemy intended to make great use of this windfall—a new defense that would enable rational humans to stand up to the madmen who wanted to plunge civilization into a Dark Age.

He raised his walker body high, extending the front pair of legs like a man raising his fists and cursing the gods.