[The guard's stance had openings. You found them.]
[Your chain-wrapped fist came down in a sequence of rapid, overlapping strikes, each one carrying the full force of a frame that had not yet discovered its ceiling. The Shadow Prison Guard was faster than a standard soldier and better armored than almost anything you had faced in this body so far. None of that was sufficient. The guard was overwhelmed by the combination of strength and speed almost immediately, retreating down the corridor under a barrage that left no gap for a counter.]
[Within seconds, the guard was trying to break outside your engagement range. Your footwork closed every distance they opened before they could use it. The relic spear swung twice more in desperate deflection attempts; you caught the shaft both times and redirected it into the wall.]
[The final strike landed squarely on the metal helmet. Adamantium fragments burst outward and clattered across the floor. The guard went down hard, their armored body hitting the metal floor with the full weight of collapsed power armor, and did not rise.]
[You raised your foot and brought it down on the breastplate twice more, deliberately, ensuring the systems were disrupted. Then you stopped.]
[The corridor was quiet again.]
[You exhaled a long breath, the air leaving your lungs carrying a faint trace of heat. The chain-wrapped fist dropped to your side. You reached down with your free hand and took the relic spear from the unconscious guard's grip, testing the balance of it briefly before letting it hang loose in your palm.]
[You stepped over the guard and continued down the corridor.]
[You had not covered much ground before your senses flagged the next approach.]
[Five of them this time. The footsteps carried more weight than the first guard, a heavier cadence that identified heavier armor even before the figures resolved out of the dim light ahead. Cataphractii Terminator plate, black with gold trim, moving in a tight combat spread across the corridor's width. The lead figure carried a storm bolter at a ready angle, the weapon's profile catching what light there was.]
["Out-of-control forbidden object! You do not have authorization to move through this facility. Stand down immediately!"]
[The bolter spoke before the echo of the command had finished.]
[Kraken penetrator rounds crossed the distance between you in a fraction of a second. You snapped the chain-wrapped fist up across the line of your head, interposing the improvised shield, and the detonations came in a rapid sequence that blew white light across your vision and set your restraint armor ringing. The force of the impacts traveled through your arms and into your shoulders, and you absorbed it and pushed forward into the fire.]
[And then the corridor changed.]
[The sound arrived first: a deep, oscillating buzz that carried a quality of enormous scale and speed, coming from behind you, filling the passage from wall to wall and floor to ceiling in the space of a single breath. Then the swarm passed over you.]
[Nanomachines. Dense enough to read as a solid mass in your peripheral vision, dark and fast-moving, flowing through the air with the purposeful, coordinated behavior of something under direction. The swarm swept past your frame without touching you and hit the five Terminator guards like a tide hitting a rock formation.]
[The sound of their armor coming apart was not loud. It was efficient. A sustained hiss of disaggregation, metal yielding to an application of force too small and too numerous to deflect, working at every joint and seal simultaneously.]
[When the swarm pulled back, five figures were lying on the floor. The Terminator plate was gone. The guards themselves were intact, breathing in slow, unconscious rhythm, their chests rising and falling with the steady pace of people deeply asleep rather than dead.]
[You stared at them for a moment.]
["David?"]
[The swarm condensed. The process took only seconds, the nanomachines contracting from their dispersed cloud into something coherent and then into something solid, a figure five meters in height, jet-black metallic surface, proportions that spoke to function before anything else. The shape was unfamiliar. The voice was not.]
["My Lord. Successful descent confirmed. Praise the Emperor."]
[You let out a slow breath.]
["David. What exactly have you become? And can you explain to me why the prison cells beneath the Palace of Terra are filled with things of this particular variety?"]
[You tilted your topknotted head slightly toward the unconscious Terminator guards, then back at the towering form beside you.]
["My Lord, the data I have access to is incomplete. But based on the structural indicators, I believe this body is a combat-configured Man of Iron from the Men of Iron Rebellion era. The hierarchy markers suggest a command-grade unit."]
[David's eyes illuminated slowly, a deep and steady blue, as he spoke.]
[You looked at the five Terminator guards again, then at David, and then you exhaled.]
["Just how capable were humans during the Dark Age of Technology, that they could produce something capable of doing that?"]
[David's response carried the particular quality of agreement delivered by someone who was simultaneously processing the same question themselves. He added, after a moment, that the current body had likely sustained significant prior damage, or carried some form of internal restriction, because even after absorbing the power armor of the downed guards as an energy source, the nanomachine swarm would require a recovery period before it could be deployed again at the same scale.]
[You nodded once to indicate you understood the constraint, then gripped the relic spear and started walking.]
[David fell in beside you, his stride long enough to match your pace without effort, and the two of you moved deeper into the facility.]
[The cells changed as you went further in. The earlier sections had held humans, criminals and political prisoners and test subjects of various kinds. The deeper you went, the nature of the containment shifted. The cell doors were heavier. The sealing mechanisms were more elaborate. And behind some of those doors, in the rare cases where the containment had held, things that were not human and had never been human existed in the particular suspension of entities that had been imprisoned long enough to lose track of why.]
[Other cells were open. The doors had been damaged, some from the outside, some from within, and the interiors were vacant. Whatever had been held there was gone, and had been gone for some time.]
[You did not slow down to investigate.]
[The corridor system was a labyrinth, but it had an underlying logic, the logic of a facility built to a deliberate plan rather than expanded organically over time. You and David moved through it at pace, reading the structure as you went, following the downward gradient that the designers had built into the layout for reasons you did not yet know.]
[Eventually the constructed corridors gave way to something older.]
[The walls changed from machined metal to natural stone, the work of geological time rather than human hands. The ceiling rose and became irregular, karst formations hanging from it in the shapes that deep water leaves in limestone over millennia. The floor was still metal, a maintenance surface laid over the natural cave bed, but around it and above it the rock had been left as it was found.]
[The cavern opened around you, large enough that your enhanced senses took a moment to map its full extent.]
[You stopped at the threshold and looked into it.]