The Octarius War was a monstrous conflict born of Imperial hubris, in which two of the galaxy's most terrible xenos species were deliberately set against one another. At its heart lay a gamble by agents of the Ordo Xenos: to blunt the rising power of an ork empire, they released a splinter of a ravenous tyranid hive fleet directly into its territory.
The ork empire of Octarius was among the most warlike in the galaxy, its greenskins hardened by endless fighting into a formidable and expanding threat. The Inquisition reasoned that pitting them against the all-consuming tyranids would grind both down and spare the Imperium two dangers at once. Instead, the plan went catastrophically awry.
Rather than annihilating each other, the two foes escalated in a spiral of mutual evolution: the orks grew bigger, tougher, and more numerous through constant war, while the tyranids adapted and multiplied by devouring them. The conflict became a self-sustaining engine of violence that swelled far beyond its intended bounds, threatening to spill across the surrounding sectors and imperil the wider galaxy. What had been conceived as a cunning masterstroke instead created a growing catastrophe, a grim lesson that some weapons, once loosed, can never be recalled.