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Burrowing Predator · Luther McIntyre IX · Segmentum Solar

Ambull

A barrel-chested tunneller with diamond-hard claws and heat-seeing eyes that digs through rock, ice and bulkheads to drag its prey into the dark.

Type: Subterranean insectoid predator
Homeworld: Luther McIntyre IX, a desert death world
Size: About four metres when fully upright
Senses: Sees deep into the infrared
Young: Borewyrms, carnivorous larvae
Status: Transport under strict Imperial bans, often smuggled

Artwork coming soon: no permitted independent art of Ambull is on file yet. Art Call

At a glance

The Ambull is a burrowing predator native to Luther McIntyre IX, a desert death world in the Segmentum Solar where the sun is so fierce that much of the native life lives underground. It is a four-limbed insectoid creature with a thick carapace, a huge barrel chest, long arms that reach almost to the ground and short, crooked legs. Its jaws open wide enough to take a man's head and shoulders in one bite. Its eyes see heat, so darkness is no protection. And its claws are hard enough to dig through rock at astonishing speed.

Ambulls have spread far beyond their homeworld. Some were brought deliberately, as mining beasts, guard animals or arena monsters. Others escaped from smugglers and private collections. Because most worlds are kinder and richer in prey than Luther McIntyre IX, escaped Ambulls tend to thrive, and their numbers can explode. Today Ambulls lurk under mining colonies, hive foundations, ice worlds and even inside the ancient structures explored by treasure hunters.

Luther McIntyre IX

The Ambull's native world is a harsh place. Luther McIntyre IX is a desert death world baked by a fierce sun, where the surface is a wasteland of rock and sand and most life has retreated underground. Its ecosystem is a hidden one, built of tunnels, caverns and burrows, where predators chase prey through the stone. The Ambull is the apex of that buried world. Its heat vision lets it find prey in total darkness, its claws let it pursue that prey through solid rock, and its armour lets it survive the crushing collapses that are part of life underground.

Life on Luther McIntyre IX is so hard that the Ambull evolved to waste nothing. It eats almost anything it can catch, it tolerates extreme heat, and it can go a long time between meals. These traits make it formidable when it is transplanted to gentler worlds. On a planet full of slow, soft, warm prey, an Ambull family can grow quickly, and the tunnels beneath a settlement can fill with hunters before anyone notices that people are going missing.

Anatomy & senses

A hunched Ambull looks smaller than it is. Its ape-like stance hides its true size, and when it rears up with its arms stretched overhead it can reach around four metres. Its body is heavily armoured with a thick carapace, and its limbs end in claws described as iron-hard or even diamond-hard. Those claws are the key to its success: an Ambull can dig through soft stone almost as quickly as a man can walk, and it has been seen tunnelling through ice as easily as sand.

Heat vision

An Ambull's eyes see deep into the infrared spectrum. In the total darkness of its tunnels, warm-blooded prey glows like a lamp. This makes the creature a nightmare for miners and soldiers who rely on darkness or cover. A man hiding behind a rock is still visible as a heat signature, and a squad huddled together in a tunnel is a beacon.

Jaws

The Ambull's most distinctive feature is its huge expandable jaws. They open wider than seems possible and close with crushing force. Ambulls hunt by grabbing prey with their claws and biting through it, and survivors of Ambull attacks often describe the jaws more vividly than anything else.

Behaviour & family life

Ambulls are social creatures. They live in family groups of several adults and four to seven young, and they dig extensive tunnel complexes that can stretch for long distances underground. Adults bring kills back from the surface to communal dens so that the young can feed. Males fight fiercely with one another when in rut.

They hunt in two main ways. Some prey stumbles into their tunnel networks and is caught in the dark. Other prey is taken on the surface at night, when the Ambulls emerge from their burrows to search for food. On their homeworld their favourite prey is the Crawler, another burrowing creature, and they chase it through soft rock at considerable speed. On other worlds they are less fussy.

Borewyrms

Ambull larvae are known as Borewyrms. They are carnivorous and dangerous in their own right, and in a swarm they can be as deadly as an adult Ambull. Borewyrms writhe through tunnels and cracks, and where adult Ambulls make their dens, Borewyrm swarms often follow.

Ambulls across the Imperium

Imperial law places the transport of Ambulls under severe bans, yet the creatures are still smuggled from world to world. Some buyers want them as attack or guard animals. Some want them for gladiatorial blood sports, where they fight criminals, slaves or other beasts. Many escape. Once loose, they dig, breed and spread, and an infestation can become impossible to remove without destroying the settlement above it.

The Ambull's resilience is remarkable. Isolated colonies in harsh, polluted environments show no genetic drift away from the original population. Some Magi Biologis have argued that the Ambull may have been engineered to resist mutation. Most consider it simply a sign of how hard its native world is.

Encounters on record

On the ice world Simia Orichalcae, Ambulls appeared in the tunnels beneath a promethium refinery during a campaign against the Necrons, killing miners. Ciaphas Cain and a Valhallan squad killed many of them in the dark, and it was speculated that they had come through a portal from some desert world.
In the training grounds of at least one Ultramarines fortress, aspirants are said to hunt Ambulls as part of their trials, learning to fight an enemy that comes from below.
Smuggled Ambulls have turned up on worlds where no one admits to importing them, digging up through mine floors and sump levels.

Ambulls in Imperial service

The Imperium has tried, many times, to tame the Ambull. Its strength, its tolerance for heat and its digging ability make it an ideal mining animal in theory. In practice, Ambulls escape almost every enclosure built to hold them. They simply dig their way out.

The greatest success has come from the Adeptus Mechanicus, which fuses Ambulls with machinery to create heavy mining constructs known as Ambots. Their brains and nervous systems are bound to specially crafted instruments, while cranial governors suppress their aggression and hunting instincts. The tunnelling instinct remains. The Ambot digs, endlessly, for its masters.

Brutal Moments

Brutal moments

The tunnel wall that breathed

A mining crew deep in a promethium tunnel stopped work when the rock wall in front of them began to warm. Their thermal readings showed something moving behind it. Before anyone could raise an alarm, the rock burst outward and an Ambull came through in a spray of stone, its jaws already open. It took the foreman in a single bite, head and shoulders gone in one crunch, and threw the rest of his body against the wall. The miners ran, but the Ambull saw their heat in the dark as clearly as if they had been carrying torches. It caught them one by one at the junctions. When rescue crews finally broke through, the tunnel walls were painted with blood and the floor was littered with boots that still had feet in them.

The nursery

Imperial soldiers clearing an Ambull nest found the den where the young were fed. The adults had been dragging prey there for weeks: miners, livestock, a missing patrol. The bodies were piled in heaps, half-eaten, and Borewyrms were writhing inside them. As the troopers stared, the pile moved and a swarm of larvae burst out and poured over their boots. Men screamed as the Borewyrms chewed through their trousers and into their legs. The flamer team burned the den with the wounded still in it, because there was no time to separate the living from the dead.

Through the bulkhead

On an asteroid mining station, an escaped Ambull tunnelled through the rock surrounding the habitation module and then through the module itself. It came through a bulkhead while the night shift slept. The atmosphere began venting through the hole it made, and men were sucked out into the void before emergency seals closed. The Ambull itself was trapped in the depressurised corridor and kept moving, slowly, for several minutes. When the crew finally reached it, the creature was dead, frozen to the deck with a half-eaten miner still in its jaws.

The arena that flooded with blood

In one Imperial arena, a governor ordered an Ambull to be released against a team of condemned prisoners for entertainment. The beast killed the prisoners quickly. Then it dug down into the arena floor and vanished. Three days later it came up in the stands. By the time the governor's guards stopped it, it had killed dozens of spectators and opened tunnels under half of the arena. The governor was later executed for importing it.

Fighting Ambulls

Use thermal masking; the Ambull sees heat.
Expect attacks from the walls and floor, not just from tunnels ahead.
Burn the nests to destroy Borewyrms.
Use heavy weapons; the carapace shrugs off light fire.
Never assume a sealed tunnel is safe. Ambulls dig new ones.

Trivia

Ambull meat is said to taste a little like grox, according to soldiers who have eaten it.
Ambull larvae are called Borewyrms.
Ambulls can tunnel through ice, rock and even metal plating.
The Mechanicus has fused Ambulls into mining constructs known as Ambots.
The Ambull has been part of the setting's bestiary since its earliest days, long before most xenos races were described.