It had to be said that while Perturabo's experiments stepped directly onto every single one of the Imperium's red lines, they were undeniably useful.
Take the Perpetual conversion, for instance. If the human race could truly be transformed into Perpetuals at low cost—setting aside any potential social chaos—the sheer evolutionary leap forward for humanity as a species was an incentive the Emperor could hardly refuse.
After all, he and Malcador had pondered this exact concept in times past. Though the initiative ultimately faded into nothingness—partly due to realizing the negative side effects that universal immortality might bring—selecting key individuals for conversion remained a sound proposition. Essential mortal administrators, Chapter Masters, and even certain Primarchs who were not true Perpetuals could benefit immensely.
Awakening one's true nature ultimately relied on the power of the Warp. While Perpetual conversion was similarly tied to the Warp, converted individuals could still operate within the physical universe at any moment.
To completely obliterate a Primarch-level Perpetual required a degree of force that was exceedingly rare, short of a Chaos God intervening directly in person.
Then there were the Necron World Engine and Celestial Array technologies. Even among the Necrons, these represented peak, top-tier engineering. If Perturabo could decipher both, the Imperium could confront the Necrons directly without fearing their high-tech Warp-lockout systems, dragging them into mutual assured destruction if necessary.
At the absolute worst, humanity now possessed the Webway as a strategic retreat. With the Necrons currently crippled, a secondary war of attrition would render their dynasties completely obsolete in short order.
Virtually all of Perturabo's current research focused on specialized countermeasures vital to human survival. Furthermore, he was not hoarding the knowledge; outside tech-priests and Techmarines were conducting independent research, forming dedicated joint task forces to collaborate.
It was simply that Perturabo achieved the most significant breakthroughs. This was not due to a reluctance to share progress, but rather because his train of thought was far too erratic. Beyond the Emperor, a handful of Perpetual scientists, and a few high archmagi, virtually no one could keep pace with him.
They were not even needed for basic laboratory support—at the highest levels of scientific research, lacking the required cognitive framework meant even routine assistance could cause critical errors.
Given the monumental importance of these technologies, Perturabo preferred working in secret rather than risking another breach by an master thief like Trazyn.
The Emperor, however, felt deeply uneasy. Though appearing radical on the surface, he remained a conservative at heart—not strictly dogmatic, but bound by a uncompromising moral threshold.
He found Perturabo's profane endeavors difficult to tolerate, yet lacked any real leverage to force his son's compliance, leaving him in a state of conflicted frustration.
"I believe you should focus your efforts on these high-technology sectors, Perturabo," the Emperor urged. "If possible, leave those profane biological experiments untouched."
"This artificial C'tan and C'tan power-cell initiative shows tremendous promise. If you feel the available shards are insufficient, order the Chapters and your brothers to excavate more Necron tomb worlds or search for additional fragments. But leave those profane creations alone."
"Refine the methods to retrieve the Second and Eleventh Primarchs, or upgrade the Imperium's existing armaments. The Solar Auxilia could certainly use your technical support, and our fleets still lack physical light-speed travel outside of Warp and Webway transit."
"There are countless valid avenues to pursue. Why fixate on these taboo fields? Listen to me—destroy them, or at least halt their development. Do not stray further down this wrong path."
The Emperor reasoned earnestly. Though he had originally initiated this dark technological path under special circumstances in the past, times were changing rapidly.
"Indeed, Warmaster," Guilliman added. "The Imperium has no need to employ such methods against its enemies. Are these biological weapons truly more practical than a Virus Bomb?"
Given his formal education and pragmatic worldview, Guilliman understood the long-term devastation bio-weapons inflicted upon worlds. Winning a world at the cost of astronomical post-war reclamation expenses stripped the victory of its strategic value.
"You don't understand," Perturabo countered. "Do you think I didn't account for that when designing them? I built specific limitations into their baseline design."
"Take the Bio-Titan synthesized from Ork and Bone-Eater genetic stock—I installed a strict limiter. The unit can only persist for seventy-two hours before its internal body temperature triggers a catastrophic thermal conversion, detonating it like a massive bomb. They are built specifically as front-line attrition fodder for Apocalypse-level warzones."
"A single Bio-Titan costs one-tenth the resources of a Warlord-class Titan, yet its tactical utility on the battlefield can exceed one. You expect me to abandon a functional war machine and write off the initial R&D expenditure?"
While Perturabo recognized their good intentions, his research had yielded zero instances of blowback to date.
Should an issue arise, he possessed the operational capacity to contain it; these trials remained strictly within controllable parameters.
In contrast, an issue like the proliferation of female Space Marines—which could expand beyond control once established—represented a scenario Perturabo was less inclined to manage.
Thus, Perturabo rarely touched taboos that might cause him to hesitate. Eldar Space Marines and biological weaponization were minor concerns to him; in his estimation, their risks paled in comparison to the precedent set by Melusine.
"Besides, shift your perspective," Perturabo argued. "Is turning these xenos into functional war slaves not the ultimate realization of our goals? The Imperium exists to save humanity, purge the alien, and reduce them to servitude."
"We have achieved that result. Employing these biological units effectively on the front lines reduces human casualties, does it not? They cost far less to manufacture than Abominable Intelligences. What does it matter if they are considered profane, so long as they secure victory? Since when did war demand fairness, morality, or high-minded ethics? When was the Imperium ever so pristine?"
Though Perturabo's argument contained clear logical leaps, the Emperor and his companions found themselves temporarily without a counter-argument.
War demanded victory by any available means, constrained only by minimal operational boundaries. For the vast majority of Imperial commanders, securing victory at the lowest possible cost in human life was the preferred course, regardless of ethical considerations.
This was the current reality of the Imperium. Even with the strategic upper hand, the fundamental nature of warfare remained brutal: preserving human lives and minimizing operational loss remained the top priority.
Had these biological weapons been deployed publicly, they might have drawn initial resistance, but opposition would dissipate quickly once their operational efficacy became apparent.
The Death Guard and the Deathwatch served as prime authorities on the matter; no forces were more adept at utilizing biological warfare.
Any minor environmental collateral damage was negligible to the broader Imperial machine. Once the Adeptus Mechanicus and Imperial engineers arrived, affected worlds could be restored to working order in short order.
High administrative reclamation costs were a concern for civil authorities, not the military forces tasked with eliminating threats to mankind.
Consequently, the Navy, Space Marine Chapters, and front-line mortal Auxilia cared little for ethical debate when survival was on the line.
Thus, while Perturabo's creations could not pass ethical review by the Emperor or the Administration, the Departmento Munitorum viewed them as yet another masterstroke by the Warmaster.
"Furthermore, these weapons won't be distributed indiscriminately," Perturabo added. "They will be reserved strictly for Apocalypse-tier engagements or specialized warzones, governed by strict operational protocols."
Unless facing large-scale warzones, the current power of the Imperial fleet rendered such weapons redundant, offering minimal cost savings.
With the argument laid out, the Emperor and his inner circle could only observe and monitor the situation, hoping these profane assets remained as stable as Perturabo claimed.
"On another note," Perturabo asked, turning to a different matter, "have there been reports of Ork activity rising across other sectors recently?"
Perturabo recalled recent complaints from Guilliman and Malcador regarding localized Ork resurgences.
"Yes," Guilliman confirmed. "It stems from the fact that their origin worlds remain intact. The four Ullanor worlds have been repurposed into major mining hubs. Their mineral density is staggering, operating almost like self-replenishing resource nodes. Despite heavy extraction, the ore veins show no signs of depletion."
"No administrator can walk away from that level of yield," Guilliman continued. "We destroyed one Ullanor previously, but given our current military dominance, we preserved the remaining worlds as vital industrial assets."
"They have been renamed and designated as major Imperial Mining Worlds, garrisoned by three rotating Chapters to suppress any Ork sprouts immediately."
Neither Guilliman nor Malcador wished to destroy assets of that scale. Four Ullanor-class worlds equaled the mineral output of an entire Segmentum. In exchange for managing periodic Ork outbreaks, the economic return was an asset no Imperial administrator could refuse.
Even a pragmatic politician like Guilliman refused to forfeit such resources.
Regardless of how rapidly the local Orks adapted, the Imperium possessed the military capacity to suppress them, extracting full value from the worlds while keeping the greenskins contained.
"That may be true," Perturabo noted, "but if Ork activity is reaching high-level reports, their numbers are already substantial. So long as the Ullanor substrates exist, greenskins will spawn continuously. Even if purged entirely in one cycle, they inevitably re-emerge from obscure corners over time."
Perturabo was intimately familiar with the Ork biological mechanism, which proved more persistent than even the Tyranid swarms. While the Tyranids evaluated tactical resource expenditure, Orks acted on impulse, often executing bizarre strategies in the heat of battle.
Fortunately, the Imperium's current anti-psyker field coverage operated at high efficiency, preventing the situation from escalating further.
"You intend to field these new biological assets against the Orks?" Angron asked, catching his brother's line of thought.
"Precisely," Perturabo confirmed. "While Orks adapt quickly, these specialized biological units provide an efficient counter. Furthermore, being comprised largely of Bio-Titans, the Orks cannot easily evolve equivalent biological countermeasures—they lack the adaptive evolution of the Tyranids."
"No matter how formidable their Stompas and Gargants are, they cannot match our Titan Legions. Testing my Bio-Titans against them could yield exceptional field data."
"These Bio-Titans are hardcoded at the base level. Though lacking true consciousness, their close-quarters capability is formidable, supplemented by dual bio-cannons adapted from Tyranid schematics."
"Their production cost is lower than a single Warhound Titan. Losing a thousand in a single engagement carries no financial weight, making the Ork warzones an ideal proving ground."
Perturabo laid out his plan. Even if the Emperor had objected, he would have eventually identified an isolated warzone to evaluate the Bio-Titans' combat performance. This initial deployment involved only Bio-Titans, keeping more extreme bio-weapons in reserve for phased testing.
The Emperor exchanged a glance with Malcador, finally offering a reluctant nod.
"Very well," the Emperor agreed. "We will dispatch these Bio-Titans to the front lines immediately. Roboute, compile a list of Chapters currently engaged on the Ork fronts so we can route the shipments."
In truth, various Iron Warriors Chapters had already quietly stockpiled these assets within their personal arsenals. Perturabo never withheld advanced hardware from his own lineage, ensuring they were equipped for extreme contingencies.
The Iron Warriors' armories were saturated with Perturabo's covert technology—ranging from bio-weapons and Transcendent C'tan fragments to Necron systems, wraithbone constructs, and the highest concentration of Abominable Intelligences in the Imperium.
It was a quiet privilege extended to his own bloodline—a level of technological sophistication no other Chapter could match.
In truth, were Imperial oversight less stringent, Perturabo would have standardized these advancements across the entirety of the Imperial armed forces.