The tree was the only thing Salvador could see before the horizon. It was a relief to the eye in the desert pitted with craters and rocks. The tree leaned into the gentle incline, as though it too pushed forwards, with unsteady carbon fibre legs, into the distance. A few grim leaves clung to one of its branches, seemingly kept alive by will alone. Salvador walked directly towards it. The bodies of a human man and young boy lay parched and shriveled at its roots.
He paused as he looked at their emaciated shapes, weighing the need to check their remains for anything of use against his programming, which said let them rest in peace. And under it, a deep revulsion for their humanity. Their unsealed eyelids revealed pale unseeing eyes. Decomposition robbed them of definition, left only slack jaws and animal husk, food for the earth beneath them. He looked up at the handful of unlikely leaves holding on to the branches above him.
He prodded a shrunken-looking canvas bag experimentally with a hinged toe. The gears in his knees whirred as he knelt to examine the prone adult figure and tapped pockets with reluctant fingers. He found a weapon and, finding it without power, dropped it by his feet. The canvas bag was filled with parchment, old and fragile. Salvador recorded the runes inscribed into it, microprocessors churning slowly. The information sat cued, along with the record of his journey, ready for upload when the satellite completed its next pass. If the satellite completed its next pass. Finally, he dropped the canvas sack, leaving the paperwork inside, at his feet by the corpses.
Salvador turned his gaze back towards the horizon. He had been walking for six hundred days, east to west, as the sun had followed him in its predictable arc. His last command had been to march, to seek satellite connection. But the blinking lights had been absent overhead; the only celestial bodies had been the sun and the moon, traversing the sky with the regularity of eons. Without further contact to the network, he had no choice but to continue to search, to hope the three blinking dots at the upper right corner of his visual cortex would resolve into the connection symbol. His coordinates would be mapped, his information recorded. He would receive further orders. But for six hundred days, the blinking dots had remained: connection pending.
He left the tree, continued his march west, into the horizon receding over the edge of the planet's belly. His thinking had become compromised over time, he knew. He had started to consider the vastness of space beyond the atmosphere in the abstract, not the vacuum scattered with rocks and dust he knew it to be but as a celestial playground. A waltz of cosmic proportion, within which his own expectations, a satellite, a connection, lay as a thin and paltry smear on a larger scheme.
Irrational thought, lingering within his processes, born of the whims of some ancient, long dead programmer. He enraged himself, indulging in this human-scale abstraction. There was no time to imagine, no place for philosophy. He had a command to follow, the path of the planets overhead, the sun and the moon, were of no consequence.
He charted the most direct course across the landscape ahead. He walked through the night and as the dawn filled the sky with soft reds behind him, silvery light tinting the clouds overhead, he continued, always westward. Every thirty days he stopped. Sat in a protected place and allowed his systems to reboot. Five hours out of every 730 was spent rebooting. When his system had re-calibrated, power cells replenished, he stood, his joints creaking as sand, rain and the constant marching took their toll on his gears and hinges, and continued his journey.
The landscape was irregular, vast plains rolled out for miles around him at times, then gave way to hideously deep ravines. More than once, Salvador's path through a desert or dense jungle stopped abruptly at an expanse of water, forcing him to seal his joints and sockets before stepping into the foamy waves. He walked along the ocean floor, navigating underwater chasms and peaks. Eventually the loamy ground would follow a steady incline, and he emerged on a sandy beach, breakers challenging his gyroscopic balance, ocean plant life clinging to his recessed ankle joints and toes.
On day 768, Salvador lost the use of his left arm. The gears inside whirred insistently, but some connection had been severed. On day 801, after staggering up a sharp incline, he sat at the peak. The weight of the useless arm was an annoyance, and the repair-needed icon in his display blinked with increasing urgency that Salvador was unable to address. Disconnecting the limb at tiny bolts and screws, he abandoned it on the loose gravel. It gathered dust, blown into its crevices by the wind, as he walked away.
It was day 847 when the edifice appeared, small and distant, on the horizon. Eventually, it towered over him as he stood recording all he could of the structure for upload. It was steel and glass, a tower into the atmosphere, as tall as the mountains he had scaled, and as sheer as some of the cliffs he had been forced to avoid, backtracking around their impassive blank faces.
The monstrosity was in ruin, shattered glass lingered in steel frames, eyes blind to the world, vegetation taking the structure into its slow embrace. The tip of the spire disappeared, a glinting, spider web fine tip in the pale blue sky. Recording the entire thing required a slow circuit around it, Salvador picked his way over and around smaller squat structures at its base, dwarfed by their tall cousin.
Some part of Salvador enjoyed this work. The architecture of humanity, crumbling though it was, far outlasted the impermanent bodies and minds that birthed them. The even, parallel lines and perfect right angles pleased his processors, and he quickly mapped the structure down to the finest detail, ensuring it could be reconstructed in some distant future. Having recorded everything he could, he picked his way through abandoned domiciles and vehicles and crossed a crumbling bridge. Before long, he found himself alone in expanses of blank, natural landscape, the vestiges of life clawing back dominance on the planet's surface.
On day 1007 the hinge in his right ankle seized up. He limped onward, under a scorching sky.
It was day 1200 when he spotted a tree in the distance across a pitted plain. It leaned into the incline of the landscape, the only thing to break the unforgiving ground for as far as Salvador's ocular lenses could see. He gravitated towards it under the glaring sun. The shadows grew long as the sun sank lower over the horizon in front of him, and the tree's shadow branches clawed, desperate and yearning, across the earth. When he stood under it, he saw others had also been drawn to its paltry shade; the skeleton of an adult human and a smaller one, a child, lay under its limbs. He surveyed the decomposition, assessing the salvage opportunities. The humans' eye sockets stared blankly at him, their teeth gleamed in an eternal grin. He picked up a weapon and, finding it out of power, tossed it to one side. At his feet a canvas bag bulged slightly. Within it, reams of parchment, inscribed with unfamiliar runes. His lenses recorded their shapes, as he flicked through the pages, eventually he returned them to the bag, which he dropped into the dust by his feet.
He turned west, as the sun melted, heavy and red, into the horizon. His last command had been to walk, to seek connection with the satellite. He had been marching 1200 days watching the three blinking dots in the upper right corner of his display. Every thirty days he would stop and perform his routine reboot. He watched the three blinking dots, waiting for it to find the connection, waiting for the satellite to pass overhead. If it ever passed overhead. The only satellites he saw were the celestial bodies, performing their gravitational arc of eons.
Under the curve of the horizon, the sun bled away, its death leaving a new deep blue sky under which Salvador limped, mechanical joints creaking, always west, through the night, across a vacant planet.