Arriving in orbit around Cog, the Inner Council of the In Purgatio Lumen debated how best to address the message from Magos Zinoviev Tevla about the riot and the revolt of the menial workers. With Lady Nichols reporting that the atmospheric shielding from Cog was off-line, it was decided that the first step should be to land in the upper levels to secure the Atmospheric generators, and then proceed down into the lower levels to ensure there were no ambushers awaiting them. Given the toxic atmosphere, only the Death Bastards were properly equipped to accompany Jequin Hos, Navigator Maturinus, Astropath Eckhart, and Explorator Felicis down to the Forge Moon.

Given the difficult flying conditions they relied on Archimedes Clement, the man who had been flying them through all their dangerous engagements even though they had never bothered to ask his name before. Conditions on the Forge Moon were indeed toxic, but Clement managed to successfully navigate to the ruined Vox Tower that had been destroyed. Landing on the surface, the party was confronted by the slowly decaying bodies of dozens of the unaugmented workers of Cog, who had been left to die in the unprotected atmosphere of the Forge Moon. They were also armed with crude laspistols, which Explorator Felicis theorized had been produced on the Moon itself during the riot.

The Vox Tower had suffered significant damage and would need repairs. Proceeding down through it, there were a few crude booby traps that were found by the keen eyes of the Death Bastards, but there were no living defenders found. Felicis’ medicae knowledge confirmed what all had suspected, any unaugmented human exposed to this atmosphere would be killed in no short order. Reaching the bottom, Navigator Maturinus and Flight Lieutenant Clement investigated the nearby habitation quarters, discovering the human workers inside appeared to have been suffocated while the servitors were functional, but offline.

The atmospheric generator itself was locked with Magos Tevla’s access code, and Felicis was left behind to work on it guarded by Reynard Tybalt and his fire-team. The harsh atmospheric conditions were draining on the Explorator, but he was confident he would get it eventually. The remaining armsmen and Explorers descended into the complex, reaching the Main Level where they discovered the central power chamber dubbed Heart of Iron – surprisingly intact despite the atmosphere ravaging this level as well. Maturinus soon realised the reasoning behind it, that the engine itself was protected by some sort of massive energy shield that kept the atmosphere as well as any intruders out.

The area was swept for activity, and the remaining service elevators were still functional and on this level. Reaching the Central Manufacturing facilities, Captain Hos was able to get into communication with Magos Tevla, who informed him that he had indeed locked out the facility after venting the atmosphere because that would engage automatic security procedures erecting the void shield around the Heart of Iron that could not be disabled, preventing any rebellious elements from reaching it. At this point, Explorator Felicis excitedly contacted the Captain informing him he had brought the Atmospheric Generators back online.

Unwilling to risk shutting down the Atmospheric systems mid power-up, the Lord-Captain and Lieutenant Clement made to secure the only functional stairway to the lower levels expecting an attack from the rioting workers. Eckhart and Maturinus would remain guarding the Heart of Iron and watching the Magos, while Explorator Felicis would attempt to remotely shut down the elevators from the Central Cogitators. At the top of the stairs, Captain Hos believed he heard a noise from the lower levels, and taking his team went to explore it, causing Eckhart to sprint through the station to try and stop him.

Felicis accessed the Central Cogitators to try and shut down the elevator, but found that the machine spirit not only lacked the ability to do this, but any knowledge that it had ever had any function in Cog, or indeed the Svard System. Believing that only the Magos had this ability, Felicis disconnected from the cogitator and frantically voxed in that the Magos had betrayed them, and he could not be trusted’. Turning to salvage what information he could, he found himself confronted by a strange floating Construct, Felicis brought up his weapon to attack it but found the thing weaved around him, and then brutally cut him down with a single blow. Knocked out and near death, with more constructs descending and the remaining Death Bastards in disarray, Valencia Mercutio dragged the Explorator to safety while the remaining troopers heroically held the line and bought him to evacuate the wounded Tech-Priest.

Captain Hos meanwhile had reached two levels down to find a man banging on the door to his chambers. He identified himself as Attilas Wolfe, one of the few survivors of this Forge Moon, and reported that Magos Tevla had in an unprovoked action vented the atmosphere, killing workers by the thousands. When he contacted the Lumen, he let the menials know that their deliverance was at hand, and in panic what few survivors there were rushed the facility to prevent the treacherous Magos from fleeing the planet. At this point learning of Felicis’ attack, Captain Hos and the Death Bastards double-timed upstairs to assist.

Navigator Maturinus was now convinced beyond doubt of the Magos’ guilt, but realised that any action would require action in the Heart of Iron, and took his and Tybalt’s fire-team there to defend the engine. Captain Hos and Astropath Eckhart met up, with Felicis recovering from his attack long enough to realise what happened. The creatures that attacked him were called Crystalwisps, a legend in the Expanse of creatures that would drain the memory of all they touched causing untold destruction. It was possible that neither the Mechanicus nor the personnel of Svard were at fault here, but were agitated by these strange Xenos creatures. Unfortunately during their discussion the Crystalwisps had exited the cogitators and went straight for the Heart of Iron. Maturinus and Tyablt’s fireteam were supported by reinforcements from Jenna Vasquez and her team, managing to down the four constructs.

Jequin Hos was on guard for enemies from the other direction, and indeed spotted two more on approach from the opposite direction. Sprinting over with Felicis, Clement and Eckhart, the Lord Captain managed to down one and injure another with his Heltor Honour Blade, and Lieutenant Clement managed to finish the thing off with his bolt pistol. At last, the atmospheric scrubbers finished work and the Forge Moon was operational again.

Meeting with Magos Tevla, the captain convinced him that this whole circumstance was an unfortunate misunderstanding. After the systems began to malfunction from the Crystalwisps, the Magos feared that the uprising had reached the moon and pre-emptively vented the atmosphere. The resulting fight between the two factions resulted in a lot of damage to Cog, and without materials from the Hollow Worlds and labourers from Svard Prime to replace what was lost, the moon would not be brought up to full operation. Magos Tevla also shared information on the crystals that had made up the creatures, and revealed his personnel had found hundreds of them scattered throughout the system over the years.

Though there was a lot of work remaining, Mechanicus personnel committed themselves to the restoration of Svard, and the Hos Dynasty returned to plan their next action…