Machines clattered and whirred, stitching the silence as it stretched. The holo-display fuzzed, flickered and then came into focus. She looked at the image and blinked. Crimson flecked the edge of the turning display. Her mind began to parse the marker runes and data abstractions. Strategic logic-conditioning shunted aside thoughts as she absorbed the updated defence data. It was an odd sensation, one that she had never got used to in all the decades of her life and service. Every now and again her thoughts and understanding would jump, like a needle on a data cylinder, and she would find herself understanding something she had not an instant before.

Bit by bit the mass of runes and symbols resolved into meaning.

The Khthonic Gate… she thought. So, it begins, just as we predicted and feared.

Starships had to translate from the warp at the edge of a system, beyond the Mandeville point, that arcane and invisible line that marked the boundary between safety and suicide. Arrive inside that point, and the competing forces of reality and paradox would rip a vessel apart. ‘Rebirth death’ the Navigators called it, when they talked of such things. Most established systems had navigation buoys and well-trodden points where it was safest to drop from the warp back into reality. Once back in the cold embrace of the void, ships then had to move in-system under the power of their real space engines. The journey from system edge to the planets of the core took even the fastest ships days.

The Solar System, though, was older than any colonised by humanity. Star travel and warp navigation had been birthed here, and over tens of thousands of years more secrets, wonders and terrors had been raised and lost within its bounds than existed in all the galaxy beyond. Two such relics of the past were the Twin Gates: stable points in space and the warp where ships could translate safely. Both tracked the orbits of planets as they orbited Sol. The Khthonic Gate lay off Pluto, and the Elysian Gate lay close to Uranus. The latter offered a further layer of paradox, as it gave ships a way to re-enter deeper in the system far beyond the point where they would be wrecked if they chanced it normally.

Anyone who planned to attack Terra in force would want to secure the Twin Gates to move their forces into the Solar System quickly. That Horus would pour everything he could into taking them was a certainty.