Volharian Tech-heresy

"Solar day 221 report: Great success. In the clearing of section T-4443, construction servitors under Magos Klien uncovered plasteel container of Octahedron shape. Dating of nearby strata dates it to Mid M23. Working on opening without damaging interior. Will report findings."

- Last report received from Volharian conversion fleet

History
In M37 the Mechanicus of Ivaldi Primus decided to attempt to found a new forge world in Vigilius in order to speed production. After considerable evaluation, the planet of Volharian was selected due to its mineral rich nature. When the conversion fleet arrived in 289.M37 to begin converting the planet into a forge world, they found the tectonic and volcanic activity of the surface to be too serious for conversion. Deciding instead to convert the moon of Volharian to a forge world and harvest Volharian for it's resources.

Beginnings of the Heresy
In 299.M37, a strange container was uncovered on the moon of Volharian. Made out of a plasteel exterior with an interior of an unidentifiable material, the Arch-Magos in charge of the project was delighted to discover that it dated back to before the Age of Strife. Choosing to leave directly overseeing the construction in order to oversee the opening of the container and examination of it's contents. For nearly two solar months he and his best tech-priests and Magos struggled to open the device as while the plasteel coating could be cut, the interior defied their best efforts. Eventually however they succeeded, and what they found within is still a matter of debate in the forge worlds of Vigilius. Some think it contained a corrupted STC database, or a cogitator infected with scrap code. Some even speculate it might have contained a Man of Iron. What ever the contents, it quickly drove all who had been exposed to it to Chaos, including the Arch-Magos in charge.

With many of the highest ranking Mechanicus adepts corrupted the rest quickly fell as well. Any that resisted were quickly killed or converted into servitors, including the fleets astropaths and navigators. Cutting off all contact with the Imperium, the construction of the forge world was altered to begin channeling the powers of the Dark Gods to make it into a Hell Forge. Simultaneously construction was begun on building enormous engines of a design dating back to the Dark age of Technology. The design of the engines was thought to have been found in the container that corrupted the Mechanicus forces, giving credit to the theory of a corrupted STC database.

Creation of the Volhar Rift
In 304.M37, after five years of silence, the Mechanicus of Ivaldi Primus began to grow concerned that something had happened to the fleet sent to Volharian. Eventually a second fleet was sent to investigate the planet to see why they had stopped responding to them. Translating into system, the second fleet was aghast to see the state Volharian's moon was in, now quite clearly devoted to the Ruinous Powers. While investigating they detected a number of the massive engines all over the system, each one in orbit of one of the systems celestial bodies. When moving to investigate the engine orbiting the moon, the corrupted fleet arrived back in system, having been delivering more of the engines to nearby systems.

Seeing the corrupted fleet outnumbered them considerably, the Arch-Magos of the loyal fleet decided to attempt to flee the system. Unfortunately the Hereteks had just arrived and were already at the system's Mandeville point. In a massive exchange of fire the loyalist's attempted to rush to the Mandeville point, resulting in almost all of their vessels being destroyed, only two ships actually making the jump to warp. The jump occurred in the middle of the Heretek fleet and caused considerable damage to the ships.

After the two loyal ships escaped, the Arch-Heretek realized that they would almost certainly return with the sector Battlefleet, a force far to large to fight. Forced to chose risking open battle with a superior force or the premature activation of the engines, he chose the latter. As the engines activated, the walls separating the materium and the warp were shattered all over the systems containing the engines, plunging them into a warp storm that the loyal ships only just escaped. Spanning a vast distance within the western part of the sector, a whole sub-sector was consumed into the warp storm.

Aftermath
As soon as the report of the two remaining ships made it back to the sector capital, the entirety of the Battlefleet Vigilius was recalled, many ships returning from other sectors. Assembled in their full might, they attempted to find a safe route into the storm, similar to the Cadian gate, but nothing could be found. Entrance or exit from the rift promised only death, and so the Lord Admiral declared that the Hereteks must have perished when their corrupt engines activated and called off the invasion. Yet the suspicion remained, especially in Ivaldi Primus, that at least some of the Hereteks must have survived. And so a watch was put on the warp storm, now named the Volhar rift, to wait for the warp storm to subside.

After nearly four millennia of watching the Volhar rift has yet to subside, and worse still, some of the suspicions were proved correct when a vessel was found in a nearby system that matched one of the known vessels of the Hereteks. On board they found only a constantly broadcasting message, that was apparently from the original Arch-Heretek. In the broadcast he claimed that Tzeench had made a deal with him, to give him STC printouts of devices not seen since the Dark Age of Technology, in return for plunging the whole sector into the warp. He claimed in the message that while his first attempt had failed to having been rushed he said that Tzeench's deal still stood and invited other Mechanicus forces to come and aid him.