Another Tzeentch warband that isn't just sorcerers

It is known across the Imperium and in the traitorous realms that the Iron Hands and their successors are devoted to technology and improving themselves by replacing their flesh with cybernetics. This earns them some suspicion, as they are in many respects made somewhat inhuman in mind as well as in body.

What is less commonly known is that this sometimes has led them into corruption by Chaos. The Iron Hands chapter themselves are tightly bound to the Adeptus Mechanicus, as are the Sons of Medusa (formed due to a schism in the Mechanicum) and even more so the Steel Confessors. But not all are as tightly tied to the Martian orthodoxy. One such was the Gorgons Perfected chapter, a third founding successor of the Red Talons who became known as innovators in tactical doctrine and for the technological improvement of their bodies in ways other than replacement by cybernetics.

In late M34, the Iron Fathers of the Gorgons Perfected experimented with a biological agent which stimulated nerve growth and seemed to improve alertness. A trial in their Scouts showed that it built up several dense nerve clusters along the spine and two inside the skull, and that as it progressed the Scouts lost both need and desire to sleep, with med-scans showing that they were able to rest their brain in shifts, with the new nerve clusters in conjunction with the Catalepsean Node fully replacing the brain functions of the sleeping portions. The elevation of those scouts to full battle-brothers proceeded, with the first two suffering brain damage from elevated cranial pressure which proved ultimately fatal. However, once this was diagnosed, it was a simple matter for the Apothecaries to administer additional hormones to increase the growth of the skull during the astartes induction process; the later portions of the process always include some growth of the skull, and increasing this growth by a modest amount was sufficient.

Emboldened by this success and its application to all new initiates of the chapter, the Gorgons Perfected carried out further experiments on themselves and their brothers, attempting a variety of biological and mechanical improvements using novel ideas, materials, and techniques. This initially proved promising, and as a decade and more elapsed, the Gorgons's boasts to their fellow Iron Hands successors became backed up by results, and several cousin-chapters made enquiries about sharing knowledge and rendering their flesh less weak.

However, as the years stretched on and the decade became a century, allied forces and cousin-chapters reported the Gorgons becoming increasingly erratic. Virtually every brother had at least one experimental modification, and in most cases three or more, and their leadership structure had become totally illegible as they awarded seniority based of their perception of 'superior capability' which became increasingly synonymous with 'heavy modification'. The death-blow came when a long-serving brother returned from a term as Watch Captain of the Deathwatch, and was shocked at the chaotic environment his chapter had become. He deserted within weeks and sought out an inquisitor and representative of the Cult Mechanicus, and a joint task force of Techpriests, Inquisitors, Skitarii, and Deathwatch brothers descended on the Gorgons's homeworld of Thenis Prime to hold them to account.

On their arrival in the battlespace, the full extent of the rot within the Gorgons became clear. The modifications of the forces opposing them extended into the outright blasphemous, with hands replaced by warpfire torches, brothers divided into parts and their limbs festooned over the surface and internals of tanks, and inhuman beasts with just enough human characteristics to remain recognizable as having once been noble astartes. The Gorgons took losses amounting to a full chapter strength, but this left a half-chapter alive to flee. Worse still, in fighting them large portions of the Mechanicus assault forces were corrupted by scrapcode and turned against the invaders. Their losses were severe enough that they disengaged from the assault once it was clear the survivors were fleeing, and did not pursue.

The remnants of the Gorgons and the newly-minted hereteks fled for dark corners of the galaxy, claiming several Space Hulks and modifying them endlessly to be fit raiding platforms. Their technology, while blasphemous, is frustratingly effective, and so repeated attempts by the Iron Hands and their successors to wipe out this stain on their name have proved futile. In the millennia since, while no Iron Hands successor chapter has wholly fallen as the Gorgons Perfected did, many pieces of such chapters have developed heretek tendencies and then been found out; those which do and survive to flee most often find their way to the Gorgons remnant, now named the Cult of the Evolving Forge, where they carry out their experiments unbound by moral scruple or laws of reality, creating new and awe-inspiring daemon engines and mutant soldiers. Not all serve Tzeentch, but their ambition and quest to change their forms into something exultant, specialized, perfect, and often sorcerous, leads it to be the most common patron.

As for the innovations the Gorgons Perfected devised in the early days of their fall, the Inquisition assessed that those marines from other chapters who had received the procedures would not be sanctioned, but using them on any new patients was forbidden and would be considered heresy and treason. The brother of the Deathwatch who alerted it to the fall of his brothers became a Blackshield, ashamed of the chapter he once had such pride in serving. His name was, at his own request, not recorded, though the record shows that a Blackshield whose first recorded operation was the sanctioning of the Gorgons went on to be a long-serving Watch Commander for the Watch Fortress Castilos Nullifact, not far distant from the Thenis system.