The signal came, sudden as lightning: a meteor of ice shot from orbit and left a shock-wave cloud plume of ablated steam. Mirasol charged forward.
The Patternists' strategy was to concentrate on the upper slopes and the landslide's rubble, a marginal niche where they hoped to excel. Their cold crater in Syrtis Major had given them some expertise in alpine species, and they hoped to exploit this strength. The landslide's long slope, far above sea level, was to be their power base. The crawler lurched downslope, blasting out a fine spray of lichenophagous bacteria.
Suddenly the air was full of birds. Across the crater, the globe on stilts had rushed down to the waterline and was laying waste the mangroves. Fine wisps of smoke showed the slicing beam of a heavy laser.
Burst after burst of birds took wing, peeling from their nests to wheel and dip in terror. At first, their frenzied cries came as a high-pitched whisper. Then, as the fear spread, the screeching echoed and reechoed, building to a mindless surf of pain. In the crater's dawn-warmed air, the scarlet motes hung in their millions, swirling and coalescing like drops of blood in free-fall.
Mirasol scattered the seeds of alpine rock crops. The crawler picked its way down the talus, spraying fertilizer into cracks and crevices. She pried up boulders and released a scattering of invertebrates: nematodes, mites, sowbugs, altered millipedes. She splattered the rocks with gelatin to feed them until the mosses and ferns took hold.
The cries of the birds were appalling. Downslope the other factions were thrashing in the muck at sea level, wreaking havoc, destroying the mangroves so that their own creations could take hold. The great snake looped and ducked through the canopy, knotting itself, ripping up swathes of mangroves by the roots. As Mirasol watched, the top of its faceted head burst open and released a cloud of bats.
The mantis crawler was methodically marching along the borders of its sector, its saw-edged arms reducing everything before it into kindling. The hourglass crawler had slashed through its territory, leaving a muddy network of fire zones. Behind it rose a wall of smoke.
It was a daring ploy. Sterilizing the sector by fire might give the new biome a slight advantage. Even a small boost could be crucial as exponential rates of growth took hold. But the Ibis Crater was a closed system. The use of fire required great care. There was only so much air within the bowl.
Mirasol worked grimly. Insects were next. They were often neglected in favor of massive sea beasts or flashy predators, but in terms of biomass, gram by gram, insects could overwhelm. She blasted a carton downslope to the shore, where it melted, releasing aquatic termites. She shoved aside flat shelves of rock, planting egg cases below their sun-warmed surfaces. She released a cloud of leaf-eating midges, their tiny bodies packed with bacteria. Within the crawler's belly, rack after automatic rack was thawed and fired through nozzles, dropped through spiracles or planted in the holes jabbed by picklike feet.
Each faction was releasing a potential world. Near the water's edge, the mantis had released a pair of things like giant black sail planes. They were swooping through the clouds of ibis, opening great sieved mouths. On the islands in the center of the crater's lake, scaled walruses clambered on the rocks, blowing steam. The stilt ball was laying out an orchard in the mangroves' wreckage. The snake had taken to the water, its faceted head leaving a wake of V-waves.
In the hourglass sector, smoke continued to rise. The fires were spreading, and the spider ran frantically along its network of zones. Mirasol watched the movement of the smoke as she released a horde of marmots and rock squirrels.
A mistake had been made. As the smoky air gushed upward in the feeble Martian gravity, a fierce valley wind of cold air from the heights flowed downward to fill the vacuum. The mangroves burned fiercely. Shattered networks of flaming branches were flying into the air.
The spider charged into the flames, smashing and trampling. Mirasol laughed, imagining demerits piling up in the judges' data banks. Her talus slopes were safe from fire. There was nothing to burn.
The ibis flock had formed a great wheeling ring above the shore. Within their scattered ranks flitted the dark shapes of airborne predators. The long plume of steam from the meteor had begun to twist and break. A sullen wind was building up.
Fire had broken out in the snake's sector. The snake was swimming in the sea's muddy waters, surrounded by bales of bright-green kelp. Before its pilot noticed, fire was already roaring through a great piled heap of the wreckage it had left on shore. There were no windbreaks left. Air poured down the denuded slope. The smoke column guttered and twisted, its black clouds alive with sparks.
A flock of ibis plunged into the cloud. Only a handful emerged; some of them were flaming visibly. Mirasol began to know fear. As smoke rose to the crater's rim, it cooled and started to fall outward and downward. A vertical whirlwind was forming, a torus of hot smoke and cold wind.
The crawler scattered seed-packed hay for pygmy mountain goats. Just before her an ibis fell from the sky with a dark squirming shape, all claws and teeth, clinging to its neck. She rushed forward and crushed the predator, then stopped and stared distractedly across the crater.
Fires were spreading with unnatural speed. Small puffs of smoke rose from a dozen places, striking large heaps of wood with uncanny precision. Her altered brain searched for a pattern. The fires springing up in the mantis sector were well beyond the reach of any falling debris.
In the spider's zone, flames had leapt the firebreaks without leaving a mark. The pattern felt wrong to her, eerily wrong, as if the destruction had a force all its own, a raging synergy that fed upon itself.
The pattern spread into a devouring crescent. Mirasol felt the dread of lost control -- the sweating fear an orbiter feels at the hiss of escaping air or the way a suicide feels at the first bright gush of blood.
Within an hour the garden sprawled beneath a hurricane of hot decay. The dense columns of smoke had flattened like thunderheads at the limits of the garden's sunken troposphere. Slowly a spark-shot gray haze, dripping ash like rain, began to ring the crater. Screaming birds circled beneath the foul torus, falling by tens and scores and hundreds. Their bodies littered the garden's sea, their bright plumage blurred with ash in a steel-gray sump.
The landcraft of the others continued to fight the flames, smashing unharmed through the fire's charred borderlands. Their efforts were useless, a pathetic ritual before the disaster.
Even the fire's malicious purity had grown tired and tainted. The oxygen was failing. The flames were dimmer and spread more slowly, releasing a dark nastiness of half-combusted smoke.
Where it spread, nothing that breathed could live. Even the flames were killed as the smoke billowed along the crater's crushed and smoldering slopes.
Mirasol watched a group of striped gazelles struggle up the barren slopes of the talus in search of air. Their dark eyes, fresh from the laboratory, rolled in timeless animal fear. Their coats were scorched, their flanks heaved, their mouths dripped foam. One by one they collapsed in convulsions, kicking at the lifeless Martian rock as they slid and fell. It was a vile sight, the image of a blighted spring.
An oblique flash of red downslope to her left attracted her attention. A large red animal was skulking among the rocks. She turned the crawler and picked her way toward it, wincing as a dark surf of poisoned smoke broke across the fretted glass.
She spotted the animal as it broke from cover. It was a scorched and gasping creature like a great red ape. She dashed forward and seized it in the crawler's arms. Held aloft, it clawed and kicked, hammering the crawler's arms with a smoldering branch. In revulsion and pity, she crushed it. Its bodice of tight-sewn ibis feathers tore, revealing blood-slicked human flesh.