"Sure, I'll guide you there. You go find it, and I'll be sure to let your House know how you died. You also pay up front before we leave."
- — Beastmaster Avon Tearl
The Killian's Bane is one of the most fearsome predators of the scattered wetlands of the infamous Death World of Burnscour in the Koronus Expanse. It was simply known as the Burnscour Wyrm, one of many dangers of the planet, until Rogue Trader Augustus Killian made the species legendary across the Expanse. Most of these snakelike creatures are at least ten metres in length, although there have been reports of ones much longer including the truly monstrous specimen Killian encountered.
Each recorded specimen is massive in size and covered with protective scales that are proof against the caustic rains which seem to pour nonstop across Burnscour. The scales along the creature's back are rougher and thicker, with many sporting short chitin spikes.
The creature gained its now infamous name many standard years ago, when Rogue Trader Augustus Killian, the beast hunter famed across the Calixis Sector and into the depths of the Expanse, took his leave on Burnscour to show off his prowess to a gathering of the sector's nobility shimmering behind protective power fields. He claimed to possess a new archeotech discovery to unveil, though exactly what it was he would not say other than it would result in a spectacular display.
Killian confidently strode to the nearby water's edge, wielding only his family's heirloom Power Sabre. He then produced an oddly shaped crystalline object, which shown with a blue-white light as he waved it over his head to the crowd's delight. Vid-captures recovered later show faces quickly turning to terror as a wyrm larger than ever seen before rose out of the swamp and far above the trees. For a long, dreadful moment, nothing moved except for the swamp water dripping onto the stunned trader, then it fell to take Killian between jaws now stretched wide enough to swallow a lander.
Theories vary if the mysterious device had somehow summoned the beast from the depths, or was designed to help him vanquish it, or perhaps protect him somehow. He was simply gone in a moment as the beast dove back into its dank home, the massive tail carelessly shattering the power field generators and plasteel tents surrounding the panicked crowd. Some insisted that Killian glowed an unearthly metallic sheen in the brief moment before he was engulfed, but this was never substantiated in the vid-captures.
House Killian was suddenly ruined in a single day, losing not only their master but also the ancient and invaluable Warrant of Trade he had always famously carried in a small stasis cylinder on his wide sash as a point of pride. Many explorers have since also lost their lives attempting to find the creature, knowing that inside is not only what could be a priceless device but also an actual Warrant, which would allow them to establish their own dynasty.
The tale spread through Port Wander's many taverns and from there into the Calixis Sector, and soon the notoriety made it a creature in high demand for the illicit fighting pits and beast arenas across the region. Seeing their favourite gladiators eaten alive, and then betting if they can escape before perishing, is often the highlight of many such affairs.
Horror of the Swamps
The creature's dorsal spikes are often covered with clumps of moss and other vegetation, giving the serpent a more shaggy appearance than other scaled creatures possess. Tech-priests of the Adeptus Mechanicus' Xenos Biologis have observed specimens deliberately diving through thick flora to drag away clumps. These plants provide a natural disguise, enough to help them stalk their prey and fool most of the larger arboreal predators. The mouth is perhaps the beast's most distinctive feature, as the jaws are only connected to the rest of the creature's skeleton with long, elastic bands of sinew and muscle. This allows the beast to open its maw extraordinarily wide, letting it swallow even the oversized creatures of Burnscour. Those it cannot swallow, it bites apart with rows of powerful fangs, each strike able to tear away huge swathes of flesh.
The Bane is amphibious, preferring areas with calm water, though some have been sighted along deep rivers. It can breathe underwater for extended durations, but maintains most of its life either floating across swamp lakes or slithering along the ground. Beastmasters from the sector have tracked some Banes several kilometres from wetlands either stalking prey or moving to new habitats, indicating that they can survive out of the water for long periods as well. For a primarily water-based creature, it can move with surprising speed across dry land and is fast enough to run down many beasts. Most Banes are relatively sedentary, however, calmly gliding along the stagnant waterways with occasional dives to search for prey swimming beneath them.
A Bane normally attacks in a swift motion, ideally attempting to engulf the quarry in a single stroke. The attack is terrifying, as the Bane can rear up to a towering height as part of its lunge. If near water, it also endeavours to swallow as much liquid as possible at the same time. This accomplishes two things, helping drown its victim but also allowing the Bane to settle rapidly to the bottom of the swamp, safely obscured from other predators. If on land, or attacking aquatic life, the Bane's powerful musculature steps in to help crush the life from its prey. Once subdued sufficiently, the Bane regurgitates the remains to rip them into more digestible chunks and then swallows them again. Luckily for those creatures sharing its habitat, a Bane feeds relatively infrequently, and a single large meal lasts it for many solar days.
Banes reproduce by releasing huge swarms of tiny offspring mere centimetres in length into the swamp, where most are quickly eaten by other predators. Even these miniature Banes are dangerous though, as if they are not killed when consumed, they continue growing and eventually bore their way out via their masticating serrated teeth. These small progeny often attach onto larger creatures, leaching off blood and flesh until large enough to drop off and eat on their own.
- Rogue Trader: Koronus Bestiary (RPG), pp. 14-15