The mounting of Counterstrike on a general scale meant that any drone approaching a feeder circuit was to be deactivated on sight. Initially, deactivation was accomplished by jamming the control signals radiated from the Datastrip system, and very soon slaughter of the drones had become wholesale. This did not mean their destruction since, when external jamming occurred, the drones' on-board microprocessors automatically took over control to execute an emergency landing and deactivation routine, allowing them to be recovered intact without suffering even the possible damage from a sudden drop.
Spartacus didn't take long to realize that drones controlled via Datastrip had a tendency not to last very long and it rapidly resorted to using relay drones universally instead. For a while this tactic proved scarcely more effective against the Army's formidable selection of electronics weaponry, but gradually Spartacus learned how to multiplex frequencies on tight control beams and to deploy multiple relays in patterns that rendered jamming progressively more difficult. Eventually, in the course of an encounter that took place deep inside the lower levels of Downtown, it succeeded in devising a fully effective counterjamming technique and within seconds the information had been flashed to all of Spartacus's constituent nodes everywhere. From that point on, reports began flooding in from all around Janus that the jamming methods used up to then were no longer working.
This was the signal to bring into action the "destroyers"—the modified drones that Fred Hayes's group had developed specifically for knocking out other drones. The mildest version of these operated by maneuvering alongside its target and extending a cutting claw to sever a prominent loop of electrical cable that formed the sole connection between the target's receiving antenna and its internal electronics. Every one of Spartacus's drones had been designed with such a loop in order to facilitate precisely this kind of operation; the loop was referred to as the carotid. Spartacus's response was to send in greater numbers of drones to saturate the defenders. The Army reacted in turn by supplementing the carotid-cutting destroyers with more lethal types which disabled their targets permanently by firing explosive pellets and, in some cases, by directing concentrated X-ray beams at their critical control circuits. The joint use of the cutters and cannon proved decisive and Spartacus continued to lose ground rapidly. Nothing got through to the vital feeder circuits and demolition of Spartacus's bridges was intensified to press the advantage to the utmost.
After a while, the observers following the battle from the Command Room noticed a slow change taking place in the tactics that Spartacus was using. As the casualties incurred in its futile attempts to force its drones through continued to mount steadily, it began pressing its attempts with progressively less determination, as if it were trying to cut its losses. Instead it seemed to be parading its drones outside effective range as bait in order to draw the destroyers into action. As soon as the destroyers descended and claimed a kill or two, Spartacus would pull its troops back out of harm's way, but not before they had seized the ones that had been knocked out, which they hauled away with them as they retreated. The subsequent progress of these souvenirs was followed and reported by observers stationed at various locations throughout Janus. The disabled drones were fed into the Janus-wide conveyor system at the nearest available loading point to where they had fallen, transported up the spokes and through the Spindle to end up being taken apart and examined in Spartacus's robot laboratories and test bays deep in Detroit. The tests performed there by probes and instruments connected into and controlled by Spartacus were followed via remote cameras by the interested scientists from the Command Room in Downtown.
Chris returned from a snack lunch and sauntered over to where Dyer was standing staring at the Crystal Ball, watching while an abrasive tool similar to a dental drill removed metal samples from the damage site of one of the latest admissions to Spartacus's casualty department. The samples were being sucked away by a vacuum tube for delivery to a battery of chromatographs, spectrometers, X-ray analyzers and other instruments.
"How's the body snatcher?" Chris inquired.
"It's figured out that something out there is screwing up its repairmen," Dyer answered. "It doesn't know what or how, though. The spheres have been looking very thoughtful."
Fred Hayes moved across toward them and waved a sheet of his latest figures in front of Chris's face.
"It doesn't know what's hit it. We've totally isolated it from five of the feeders. At this rate we'll be shutting it down within a few hours at the most. It has to be really sweating now."
At least seven—any seven—of the feeder circuits were needed to keep all of the backup stations functioning. Thus if Spartacus could be reduced to having connections to just three of them, those three could then be switched off at the fusion plant and Spartacus would be de-energized while the backups continued running. From what Fred had just said, it only remained for two more of the feeders to be cleared before that point would be reached.
"What are you predicting then, Chief?" Chris asked Dyer. "Has Spartacus had it or are we going to see more yet?"
Before Dyer could answer, an excited stir broke out among Krantz and the people standing around his console up on the dais. All the faces an the Command Floor below turned and looked up instinctively.
"We've just received a message from one of the observers in Detroit," Krantz told them. "Spartacus has started manufacturing drones with modified designs. The new ones don't have carotid loops. Also their key parts have been moved inside and protected by thickened and reinforced outer casings. It appears that Spartacus has reinvented armor."
"Bloody hell!" Chris exclaimed. "It's sending in flying tanks."
"Sounds like it," Dyer agreed in a sober voice. "Does that answer your question?"
At that moment a second chorus of gasps and mutterings arose around the console at which Linsay's team of officers were gathered. All the faces turned in that direction. Linsay came through a few seconds later on one of the screens in front of Krantz.
"It looks like what we thought might happen," Linsay declared without preliminaries.
"Dropout?" Krantz inquired. The general nodded.
"Everywhere. They're going down like flies."
All over Janus, the whole armada of destroyers had suddenly stopped functioning.