When the thirteenth night fell, Fengluns was startled by news from his guards.
Those metal hulks were forming ranks on the plain.
Ever since those mechanical forces had descended from the sky that day, all news of the Insects had ceased to reach the Fortress.
The Planetary Defence Force troops sent to follow them had moved beyond the Fortress's supply range after two days and ultimately had to abandon their pursuit.
Across the vast landscape, aside from the wreckage of former Imperial forces and collapsed buildings, there were only Tyranid corpses littering the ground.
Those silent killing machines had slaughtered every bug in sight indiscriminately, without rest or sleep.
The Poisonous Air and strange spore clouds had been purged by the searing heat of plasma.
Wherever those steel reapers passed, there was almost no additional pollution hazard beyond a slight rise in radiation.
Even the Fortress itself had received good news.
The Astropaths within the Fortress described what they sensed in the Warp. Although Astropathic Communication remained obstructed, the terrifying shadow enveloping the planet had begun to recede.
Fengluns began sending most of the Fortress's civilians out alongside the Planetary Defense Force to clear away the Tyranid remains covering the surface.
And now, those metal machines had appeared near the Fortress once more.
When Fengluns climbed the firing tower again, he could just make out that only the lower base of the enormous Titan remained. The Castellans were dismantling the Apocalypse Titan's three massive supporting legs.
The machine intelligence Servitors had finished dismantling the temporary Maintenance Center, and the enormous metal Fortress had disappeared.
The compartment structures were folded back together and consolidated, leaving enormous rectangular cargo containers on the ground. Undamaged Sentinels walked into the containers one by one and entered suspended animation, while the other damaged units were