[The passage was dark and narrow, built for access rather than movement at your current scale. You went through it at pace regardless, the golden scepter held horizontally at your waist, the weapon's weight balanced against your stride without effort. David's footsteps came behind you, each one a deliberate impact.]
[Malcador's directions had been precise. The passage ran beneath the palace complex and came up inside the outer defensive perimeter of the Palace of Terra itself, a route known to a very small number of people and built for exactly this kind of situation.]
[The timing of your arrival was what it was. A lost Primarch appearing mid-siege, without a Legion at their back, without the context of the broader strategic picture that Rogal Dorn was managing from whatever position he currently occupied: the contribution was finite. You understood that. But finite was not nothing. Every loyal warrior whose death you prevented was a warrior who could continue fighting, and the Siege had been grinding on long enough that every such saving had compounding value.]
[David accelerated ahead of you without warning.]
[His black metal arm connected with the internal face of a thick metal door and the door stopped being a door. It came apart outward in a burst of fragments and landed somewhere beyond the threshold in several pieces, and through the gap came light: genuine light, the kind that came from a sky rather than a lamp, bright enough after the darkness of the passage to be momentarily overwhelming even to your enhanced vision.]
[The sounds arrived with the light.]
[The discharge of lasweapons in sustained fire, hundreds of them layered into a continuous roar. The engines of atmospheric fighters cutting through air above the walls at speeds that compressed the sound of them into a hard streak. The deep, rhythmic impact of artillery against void shields. And underneath all of it, closer, the sounds of individual combat: chain axes and power swords, the bark of bolt weapons, the particular noise that chainswords made when they found armor.]
[You stepped through.]
[The first thing your foot found was a pile of flyers. You looked down. Towering figures in blue armor, promotional text proclaiming an imminent arrival. Ultramarines. Guilliman. Someone below had been spreading the word that relief was coming, and the word had made it this far in paper form before the battle had overtaken whoever had been carrying it.]
[You looked up.]
[Above the Palace of Terra, the void shields held. They covered the palace complex like an inverted bowl of compressed light, each artillery impact landing against the outer surface and dispersing across the field rather than penetrating, the accumulated fire leaving the shields stressed but intact. Beyond the shields, beyond the walls, the sky over Terra itself told a different story. The air carried a fine white ash, light and pervasive, settling on every surface in a continuous slow drift. It was not snow. It was everything outside the palace walls that had burned, the cities and the people and the structures of centuries, reduced and carried on the wind.]
[You registered this without stopping.]
[A squad of Iron Warriors Terminators had teleported to the top of the city walls nearby, their arrival scattering the Solar Auxilia soldiers who had been holding that section of the wall. The mortals were running, their lines broken, the Terminators moving through them with the particular efficiency of Chaos Space Marines who had stopped thinking of loyalists as opponents and started thinking of them as material.]
[You raised your hand and pointed.]
[David came apart.]
[The nanomachine swarm erupted from the form he had been maintaining and swept forward across the wall's surface, covering the distance to the Iron Warriors Terminators in a second and enveloping them completely. The Terminator armor was heavy and ancient and built to withstand almost everything that the Age of Darkness had been able to throw at it. It was not built to withstand the disaggregation pressure of a Men of Iron command unit operating at full output. The Terminators and their armor and everything they had been carrying were absorbed into the swarm's energy budget and accounted for.]
[The Solar Auxilia soldiers stood in the aftermath and stared at the swarm, and then at the towering figure that had stepped out of the passage behind it.]
[You did not let them kneel.]
[You told them they had held well and fought with honour, and you asked them where Rogal Dorn was. A mortal officer pointed along the wall with the expression of someone who was still processing what they had just witnessed and was defaulting to trained responses while their mind caught up. You nodded, and moved.]
[The wall was a battlefield for its entire length in every direction. Rebel Astartes had established footholds at multiple points, Word Bearers and World Eaters and Iron Warriors holding sections they had taken against the loyalists still fighting to reclaim them. Chaos Daemons had manifested alongside the rebel Legions in the places where the wards had failed, the things of the Warp moving through the smoke and the ash with the satisfaction of entities who had waited for this moment for a very long time.]
[You and David moved through it.]
[David had grown. The nanomachine swarm had absorbed enough energy sources during its work on the walls that its total mass had increased noticeably, and it moved with the kind of momentum that made even Chaos Daemons recalculate their immediate priorities. You moved alongside it, and the mutations the siege-air and the combat were drawing out of the Experimental Subject Eleven body were accelerating: both your arms had fully transformed into enormous axes of dense flesh and bone, and the colorful scales had returned across your skin in full coverage, the iridescent pattern shifting under the light of a burning world.]
[You were aware that you did not look like a loyalist Primarch. You looked like something that had crawled out of the same Warp-touched conditions that had produced the things you were fighting. The mortal warriors you passed gave you the same wide berth they gave everything else.]
[You kept moving and kept clearing the wall ahead of you, and kept looking for Rogal Dorn.]
[Your senses found the engagement before your eyes did.]
[Two fighters. One in the tattered remnants of Imperial Fists power armor, black sword moving in a pattern that was aggressive and technically precise and utterly without hesitation: a warrior who had been fighting for a very long time and had no interest in stopping. The other bare-armed, World Eaters markings on what armor remained, chain axes swinging in the undirected fury that Khorne's touch produced in the warriors it chose.]
[You cleared the distance in one push, launching from the wall surface and coming down between them.]
[The Imperial Fist's magnetic boots fired and drove him backward the moment you landed, the instinct of a trained warrior creating space from an unknown variable before his conscious mind had classified the threat. The World Eater classified nothing and adjusted nothing and came at you with both chain axes regardless.]
[You caught the swing on one flesh-axe arm, let the chain teeth scrape across the dense bone, and drove the other arm across the World Eater's torso. The blow separated him at roughly the midpoint. You caught the falling upper half before it could become a problem and sent it over the wall's edge.]
[The Imperial Fist had not lowered his sword.]
["Disgusting creature! Who are you? Why are you assisting me? Name yourself, now!"]
[You turned your head.]
[The Astartes holding the black sword had the bearing of someone who had been fighting since before the Siege began and had found, somewhere in the process, a state of absolute readiness that did not require rest or doubt or any of the other things that normal people needed. The sword was ancient and the grip on it was completely certain and the suspicion in his voice was not hostility: it was the professional caution of someone who understood that appearances in a Warp-touched battlefield were not reliable indicators of allegiance.]
["Unless I am mistaken," you said, your voice carrying out of the ugly, scale-covered face with more calm than the face's current configuration had any right to produce, "that weapon in your hand is the Black Sword. Sigismund. Truly a son of Dorn — but your manner of greeting leaves something to be desired."]
[You let the smile reach the parts of your face that were still capable of it.]
["I am Rogal Dorn's brother. A loyalist Primarch who took a wrong turn."]