Underfoot
The machine had outlived its makers. It had not outlived its instructions.
An Imperial expedition discovers a lightless construct enclosing an entire star. Its makers are nowhere to be found, but when Titans breach the surface, the explorers discover that something inside has continued working for an impossibly long time.
The star was missing.
That was the first conclusion reached aboard the Imperial survey cruiser Resolute Testament, and for seventeen minutes it remained the least impossible explanation available.
The vessel had translated from the Immaterium two million kilometres above the system's predicted ecliptic. Navigational archives identified a stable yellow star, seven planetary bodies and a debris belt of no strategic value.
There was no yellow star.
There were no planets.
There was only darkness.
Not the darkness of empty space.
Something was there.
The distinction took the bridge crew several minutes to accept.
Stars vanished behind it.
Not dimmed.
Not obscured by dust.
They simply ended against an absence so complete that the eye attempted to interpret it as empty void.
Auspex returns described a mass consistent with the missing star.
Gravitic instruments confirmed it.
Then confirmed it again.
The system's expected stellar mass had not vanished.
It was still there.
Hidden.
Captain Lysa Veran stood beneath the bridge hololith and watched the void slowly acquire a shape.
"Magnify."
The darkness expanded.
Nothing emerged.
"Again."
The image enlarged until individual pixels of stellar background fractured into artificial colour.
Still nothing.
There was no glimmer of reflected starlight.
No surface glow.
No aurora.
No thermal bloom.
No variation sufficient for a human eye to recognize texture.
Only a curve defined by the disappearance of everything behind it.
Magos Explorator Hester-9 inclined the brass latticework that had replaced most of his head.
"We are not observing an absence of illumination."
Veran looked toward him.
"Then what are we observing?"
"A surface."
Silence spread across the bridge.
One of the junior officers laughed.
Nobody joined him.
Hester-9 continued.
"Estimated radius: one hundred and forty-eight million kilometres."
The officer stopped laughing.
The hololith adjusted.
A faint geometric curve appeared, generated entirely by the position of background stars disappearing behind the object.
It was almost exactly where the orbit of the system's innermost worlds should have been.
Captain Veran looked at the black disc.
"That would place the star..."
"Inside."
"Inside what?"
"That is presently undefined."
"A station?"
"No."
"A fortress?"
"Insufficient data."
"A weapon?"
The Magos paused.
"Everything is a weapon if approached with sufficient enthusiasm."
Veran stared at him.
"Can you determine what it is made of?"
"No."
"How old?"
"No."
"Whether anything aboard is alive?"
"No."
"Whether it knows we're here?"
"No."
Veran looked again at the impossible curve swallowing half the hololith.
"Send the astropathic priority signal."
"Classification?" asked the vox officer.
She considered the black sphere.
"All of them."
Forty-three days later, the first reinforcements arrived.
Then more.
Then more.
An Explorator flotilla translated into the system beneath the red glow of tortured reality.
Imperial Navy escorts followed.
Mechanicus survey vessels took stations scattered across a fraction of the object's curvature.
More ships waited beyond them.
Troop transports.
Skitarii carriers.
Heavy landers.
Munitorum vessels whose holds contained enough ammunition to reduce cities to memory.
Specialist vessels arrived bearing excavation machinery, xenobiologists, atmospheric processors, enginseers, archaeotechnicians and several competing groups of priests who disagreed profoundly about the theological implications of the discovery.
The last arrivals carried Titans.
Three Warhounds.
Two Reavers.
And the Warlord Invictus Gratia.
The Imperium did not know what lay inside the sphere.
Therefore it had brought enough force to invade it.
For nine days, nothing happened.
The Imperial fleet transmitted in High Gothic.
Low Gothic.
Binary cant.
Mathematical sequences.
Gravitational pulses.
Electromagnetic patterns.
Mechanicus invocations normally reserved for machine intelligences of uncertain provenance.
One particularly devoted cohort broadcast hymns continuously for thirty-one hours.
The sphere remained black.
It emitted almost nothing.
Its surface reflected almost nothing.
Even active auspex struggled against it. Measurements returned in fragments, as though the instruments were attempting to describe a horizon where none should exist.
Survey craft approached within a few hundred kilometres.
Nothing reacted.
Servitor probes touched the surface.
Nothing reacted.
One probe remained there for six hours before returning.
Its hull showed no contamination, no radiation exposure and no measurable residue.
It had simply touched something black, smooth and impossibly large.
On the tenth day, Captain Veran was watching another survey sweep when a line appeared across the darkness.
At first she assumed an imaging fault.
Then the line widened.
"Magos."
Hester-9 was already turning toward it.
"Confirmed."
The line stretched beyond the hololithic field.
Segments of the sphere were moving.
No jets fired.
No light escaped from the seams.
No detectable mechanism pushed the structure aside.
A section of material larger than many Imperial worlds simply withdrew into the surrounding shell.
Behind it waited a rectangular darkness.
Veran watched the measurements resolve.
"How large?"
Hester-9 answered.
She thought she had misheard him.
"Repeat."
He did.
The opening was more than sufficient for a battleship.
Several abreast.
"Did we cause that?"
"Unknown."
"Did it respond to one of our transmissions?"
"Unknown."
"Is something inviting us inside?"
Hester-9 was silent for several seconds.
"Unknown."
Captain Veran sighed.
"At least we remain consistent."
The first vessel through was unmanned.
Nothing destroyed it.
The second carried servitors.
Nothing destroyed them.
The third carried Skitarii.
Nothing destroyed them either.
The Imperium became confident.
This was generally when trouble began.
The Resolute Testament crossed the threshold twelve hours later.
Captain Veran stood on the bridge as the exterior universe vanished behind them.
The passage ahead was large enough that the cruiser did not illuminate both walls at once.
Its searchlights reached into darkness and found planes of black material interrupted by distant ribs, braces and structures whose dimensions exceeded the ship itself.
The cruiser proceeded at combat readiness.
Nothing challenged it.
Hundreds of kilometres passed.
Then thousands.
Secondary passages branched away from the primary channel.
Some were large enough for capital vessels.
Others appeared only as narrow slots until measurements revealed widths of several kilometres.
Occasionally the searchlights caught structures crossing the darkness far away.
Columns.
Cables.
Bridges.
Perhaps.
The words became unreliable at this scale.
No markings explained them.
No heraldry decorated them.
No warning lights blinked.
No vox traffic filled the silence.
There were no bodies.
No wreckage.
No dust.
No abandoned transports.
No impact scars.
No evidence that anyone had ever fled.
The place did not feel abandoned.
Abandoned things decayed.
This had simply become quiet.
That difference began appearing in expedition reports long before anyone was willing to discuss it aloud.
They reached the first open interior space sixteen hours after crossing the shell.
Captain Veran initially refused to believe the dimensions.
The chamber extended beyond visual range.
Its ceiling hung several kilometres overhead.
Its far wall was lost beyond the curvature of the internal terrain.
Terrain.
That was the word that unsettled her.
There was soil below.
Water.
Vegetation.
A forest stretched beneath the ship.
Not hydroponic racks.
Not fungal vats.
Not the carefully rationed greenery of an Imperial vessel.
Forest.
Trees rose hundreds of metres beneath a diffuse pale light for which no source could immediately be found.
Rivers moved through valleys.
Mist gathered over low ground.
Cloud formed beneath the ceiling.
The atmosphere was breathable.
The temperature varied subtly with elevation.
The water contained microorganisms.
The soil contained more.
Flying organisms moved between the upper branches.
"Life signs?" Veran asked.
"Uncountable," said Hester-9.
"Intelligent?"
"Unknown."
She looked at him.
"You enjoy saying that."
"I enjoy accuracy."
Within six hours, the first landing zone had been established.
The Titans came down first.
Princeps Acastia Veyr watched the alien forest rise toward Invictus Gratia through the manifold.
She had walked the God-Engine through hive cities.
She had crossed plains beneath artillery fire.
She had watched lesser war machines scatter before her shadow.
She had stood above fortress walls while populations fled below.
Here, her Titan seemed strangely proportioned.
Too small for the landscape.
The trees were not larger than Invictus Gratia.
That would have been easier.
They were simply numerous enough, and the chamber vast enough, that the Warlord no longer dominated what surrounded it.
The ceiling was so high that it became atmosphere.
The walls were so distant that they became horizon.
Behind her landed the two Reavers.
Then the Warhounds.
Then Knights.
Skitarii cohorts.
Tracked crawlers.
Macro-haulers.
Survey platforms.
Servitors.
Engineering detachments.
Xenobiological teams.
Portable reactors.
Enough personnel and armour to form the beginning of an occupation force.
Nothing opposed them.
The Titans formed the centre of the expedition.
Naturally.
They were God-Engines.
There was very little in the known galaxy that could not be made more secure by positioning a Warlord Titan beside it.
For three hours, Invictus Gratia stood motionless while temporary fortifications were established around its feet.
Veyr watched Skitarii become dots beneath her.
Beyond them, the forest continued.
Nothing moved toward them.
Nothing warned them away.
Nothing acknowledged that the Imperium of Man had arrived.
Veyr found that more irritating than hostility.
They moved deeper.
The forest eventually gave way to an open plain divided by enormous channels of slow-moving water.
On the horizon rose structures that might have been buildings.
Or machinery.
Or mountains made with intent.
They could not tell.
Everything resisted scale.
A shape that appeared close required hours to approach.
A ridge became a wall.
A wall became a structure kilometres thick.
What had looked like a narrow gap became a passage wide enough for the entire expedition to enter without breaking formation.
They passed beneath arches that could have accommodated voidships.
They crossed bridges so broad that several Titans marched abreast without approaching an edge.
They encountered openings in the floor whose opposite sides could not be seen.
The Mechanicus marked each one for later investigation.
The list became very long.
The Mechanicus grew increasingly certain that they had found a technological relic without equal.
Some spoke quietly of Standard Template origins.
Others rejected this as absurd.
Several suggested pre-human construction.
One suggested Necron provenance and was immediately surrounded by sixteen people explaining why he was wrong.
Another proposed that the entire structure might be a tomb.
Hester-9 asked what sort of tomb required forests.
The discussion continued for six hours.
Princeps Veyr cared little.
Whatever had built the place had built it strongly.
Whatever had lived here was apparently gone.
And whatever secrets remained would eventually belong to the Imperium.
That was how such things worked.
On the third day, they entered another garden.
At least, that was what the expedition had begun calling such regions.
This one was different.
The vegetation had been arranged.
Not into rows.
Not into beds.
Nothing so comprehensible.
But the distribution was too deliberate to be entirely natural.
Dense stands of towering growth alternated with low open regions. Water moved through channels that curved with improbable precision. Stone formations emerged from the soil at intervals too regular to be geological and too irregular to be architecture.
Plants resembling broad translucent fans opened toward the unseen source of light.
Others grew in tight metallic spirals close to the ground.
Some shifted when the expedition passed.
Not away.
Simply shifted.
Small flying organisms moved through the canopy.
Something with too many legs crossed the path of a Warhound and vanished into the undergrowth.
The Warhound's Princeps requested permission to shoot it.
Veyr denied the request.
"We are explorers today."
"Yes, Princeps."
"Tomorrow remains available."
The expedition continued.
They moved in disciplined formation.
Warlord at centre.
Reavers behind.
Warhounds ranging ahead and to the sides.
Knights between the larger machines.
Skitarii and crawlers filling the spaces between them.
Thousands of tonnes of armour advancing through a silent garden beneath a ceiling hidden in haze.
For almost an hour, nothing happened.
Moderati Solan noticed the eyes.
"Princeps."
Veyr was examining the distant structures through the manifold.
"What?"
"Above us."
"Specify."
"The ceiling."
She looked upward.
At first she saw nothing.
The ceiling was kilometres above them, lost in haze and shadow.
Then something opened.
A circle of pale light.
Then another.
Then twenty more.
The largest was perhaps twelve feet across.
The smallest were little more than pinpricks at that distance.
They were not lights.
They moved.
Focused.
Contracted.
Eyes.
Hundreds of them.
Perhaps thousands.
Set into something vast and dark that had been hanging above the expedition since they entered the chamber.
The entire Titan maniple stopped.
Skitarii weapons rose.
Knights pivoted.
Targeting systems began painting the ceiling.
"Contact," said Solan.
"I can see it."
The thing moved.
A shape separated from the darkness.
A torso.
Or something sufficiently similar that Veyr's mind chose the word despite the scale.
There were no legs.
The body vanished upward into machinery embedded in the ceiling.
Arms unfolded from it.
Two at first.
Then four.
Then more.
Each was hundreds of metres long.
The first pair descended toward the forest.
Hands opened at their ends.
Then the fingers opened.
Veyr's targeting systems struggled to interpret what followed.
Each finger divided.
Joints rotated.
Smaller arms unfolded from within the larger hand.
Those arms ended in hands of their own.
Those hands unfolded again.
Arms became hands.
Hands became arms.
Again.
And again.
Some retained five fingers.
Others divided into dozens.
Some ended in broad manipulators large enough to close around a Titan.
Others narrowed until the auspex could no longer distinguish one moving component from another.
One vast limb contained within itself an entire hierarchy of smaller limbs.
A hand became a forest of arms.
Every arm became another set of hands.
And somewhere inside those hands were movements too small for the Warlord's sensors to resolve.
Nobody fired.
The presence ignored them.
One enormous hand reached into the forest.
Smaller limbs spread through the canopy.
A dead branch the size of a hab-block was removed from a tree.
Another manipulator descended into the soil.
It lifted a root system without tearing it.
Smaller hands separated individual strands.
Something was placed beneath them.
The roots were lowered again.
Soil closed around them.
Another arm crossed half the chamber and lowered itself beside a pool.
Hundreds of its smaller manipulators moved simultaneously through reeds along the bank.
Some removed dead growth.
Some rearranged stones.
Some touched the surface of the water and withdrew.
A third limb moved through a stand of vegetation, pruning leaves one by one.
Princeps Veyr stared upward.
"It is gardening."
Solan took several seconds to answer.
"Yes, Princeps."
"That thing is gardening."
"It appears so."
Veyr had doctrine for orbital assault.
Doctrine for city-breaking.
Doctrine for daemonic manifestation.
Doctrine for enemy Titans.
She had no doctrine for this.
Then all of the eyes turned toward them.
Not some.
All.
The change was instantaneous.
Hundreds of pale circles shifted through the darkness until the entire face of the presence appeared focused upon the expedition.
Veyr felt Invictus Gratia tense around her as targeting solutions flooded the manifold.
"Weapons hold."
No one questioned her.
One of the enormous arms moved.
There was no warning.
No sense of acceleration.
One moment it hung above them.
The next, a hand surrounded Invictus Gratia.
Alarms erupted.
"CONTACT!"
"Void shields stable!"
"Reactor stable!"
"Motive systems—"
The ground disappeared.
Veyr felt no impact.
No crushing force.
No acceleration sufficient to explain what the manifold was showing her.
The Warlord was rising.
Fast.
Faster than any machine of its mass had any right to move.
The forest dropped away beneath her.
"Fire!" someone shouted across the battlegroup vox.
"NEGATIVE!" Veyr roared.
The landscape moved sideways.
Not blurred.
Moved.
For one impossible instant the Titan's positional systems disagreed with one another by more than three kilometres.
The inertial monitors reported almost nothing useful.
Solan's voice had gone very quiet.
"Princeps... that is not possible."
Veyr had seen the Warp.
She had watched distance become meaningless.
She had felt space turn itself inside out around a ship.
This felt nothing like it.
That somehow made it worse.
The Warlord descended.
Its feet touched soil.
The great hand remained around it for less than a second.
Long enough for the Titan's balance systems to settle.
Then it released.
Invictus Gratia stood upright.
Three point four kilometres from where it had been.
Before Veyr could speak, the first Reaver arrived beside her.
Then the second.
A Warhound appeared beyond them.
Another was placed down twenty metres away.
A Knight vanished from the original formation and appeared beside the Warhound.
Macro-haulers followed.
Tracked crawlers.
Survey platforms.
Portable reactors.
One broad hand moved the largest machines.
Its fingers unfolded into smaller arms that gathered the Knights.
Those fingers opened again.
Smaller hands lifted crawlers.
Another generation unfolded from them and began collecting servitors.
Then Skitarii.
Then individual pieces of equipment.
Veyr watched a manipulator no larger than a human arm descend beside a squad of Skitarii.
Five smaller hands opened from it.
Each gently closed around a single armoured soldier.
They disappeared upward.
The soldiers reappeared seconds later three kilometres away, standing upright, weapons still in their hands.
One had dropped his rifle.
A smaller hand arrived carrying it.
Placed it at his feet.
Withdrew.
No one moved.
The relocation spread through the expedition faster than commands could follow it.
Thousands of tonnes of armour.
Hundreds of vehicles.
Thousands of personnel.
Equipment.
Servitors.
Supply pallets.
Field generators.
Everything within the formation.
Not thrown.
Not dragged.
Not scattered.
Placed.
Carefully.
The expedition reassembled several kilometres away.
Not exactly as it had been.
But close.
The Titans remained near the centre.
The vehicles remained grouped.
Infantry units had largely been kept together.
Even cargo had been deposited near the units that had carried it.
As though something had understood the shape of their formation well enough to move it without bothering to preserve it perfectly.
Nothing was damaged.
No one was dead.
No one was even injured.
For several seconds there was only vox static.
Then the enormous eyes looked away.
The hands folded back into hands.
Arms folded into fingers.
The impossible geometry withdrew toward the ceiling.
One remaining manipulator descended into the place where Invictus Gratia had been standing.
A hand opened.
Its fingers became smaller hands.
Those divided again.
And again.
Until a final manipulator descended into the shallow depression left by the Warlord's foot.
Something was there.
Small.
So small that none of the expedition's sensors had marked it as significant.
A pale knot of growth lay pressed into the soil.
No wider than a human hand.
The tiny manipulator lifted it.
Another loosened the ground beneath it.
Another adjusted something Veyr could not see.
The growth was lowered back into place.
Soil was drawn gently around it.
The final hand remained there for several seconds.
Then withdrew.
Far above, the greater arms resumed their work.
A branch was pruned.
A root was moved.
Water shifted through a channel.
The garden continued.
Princeps Veyr stood inside the manifold of a God-Engine capable of levelling cities.
Three kilometres away, the place where that God-Engine had stood was being tended by something that had apparently considered moving the entire Imperial expedition easier than working around it.
For the first time since entering the sphere, nobody asked what secrets they would find deeper inside.
Nobody discussed salvage rights.
Nobody proposed claiming the structure in the name of Mars.
Nobody asked whether the thing above them could be destroyed.
There was a more immediate question.
What, exactly, had just decided where the Imperium was allowed to stand?