Recruited by Company 44, Id undergoes training.

Id remembers his training as a blurred sequence of incidents; a disjointed hallucination:
Waking from a daze of information to realise he is in a desert, the sand painfully hot on his bare feet. Squinting at the distant horizon he surveys the impossible amount of space surrounding him, an inversion of the City’s density, almost an affront.
A blur of feet and hands, knocking him down again and again. The mechanical helps him up, explains his mistake, and bashes him to the ground again. He is the mech’s friend but does not know why.
A long white room, tiled, with metal drains in the floor. A doctor approaches, smiling, reaching to shake his hand. The doctor’s touch stings, and when Id moves his arm it leaves trails in the air, a tiny sphere of blood on his palm leaving its own blurred arc of red in the haze that is his hand.
Hours of meditation with the motionless mechanical. Returning again and again to breath and to posture, till the intervals between returning grow, and so his attention, awareness, concentration, his presence in the moment, all deepen. The machine tells him how with practice he may embrace a sensation - tiredness, pain, sadness, happiness - and draw it to him, passing through into a clarity where the sensation no longer rules him.
Scared and stunned stupid by the unfamiliar things all around, things he has never known: endless heat, night, strong wind, sky. Of course he has experienced all these in simulations, but now, real, they contain a totality he had never suspected.
His need for painkillers reaching a horrific intensity in which his every thought is structured around the absolute, desperate necessity of them. The days as this gradually abates: shaken, screamed and sweated from him. The weeks afterwards, during which they trouble his mind with less and less frequency, though still sometimes with a surprising, painful grip.
Climbing a sheer cliff. The desert is spread beneath him, a sheet of light. Hot, aching, and frightened by his precarious position he is nevertheless pleased by the climb, his body capable of the tasks he sets it.
Lying on his back, unable to sleep. He feels like tearing himself open, ripping into his stomach, clawing into his nasal cavity and wrenching his skull apart. He wills himself to run, to escape the mechanical and allow the desert to shred him, but he cannot move.
Intimations of surgery. Bruising. Pain in bands around his head that fades over time, leaving a wonderful sense of lightness. Days, and then weeks, without a headache or migraine, till he can almost forget them.
The mechanical patiently teaching him. It lets him practice his new skills in a simulator set under the canyon wall. It gives him lessons on nanotechnology, biotechnology, on the strange tricks of passive and aggressive communication. He learns to use the Company’s AI - which, more advanced than the City Computer, holds the simpler machine hostage through viral threats, routinely invading and secretly raping it.
Seeing a gap in the mechanical’s defence he spins and delivers a sweeping kick to its head, knocking it over. It shows pleasure at his progress and they fight again, though now its speed is doubled. He looks on, appalled, as it kicks away his legs and cracks him in the side of the head, then helps him stand, patiently explaining his error.
Endless presentations on the details of the worlds he may encounter: common environments, typical lifeforms, frequently encountered social minutiae, local economies, the role of Company 44 in a world’s power matrix. He scrapes the surface of facts without end.
Waking terrified each morning, barely escaping the following abyss. He goes to shout, but lapses into forgetfulness before he even sits up.
The mechanical correcting his every movement. It teaches fluidity, how to move silently, how to pass from shadow to shadow. It wakes him every night to walk a dry creek bed filled with loose pebbles till he is near silent, and even the big spindle legged insects who come out after dusk miss his approach.
Learning to speak semiotic, so he may be understood in all languages. This is the hardest skill the mechanical teaches, one he cannot master in his short time with it - one that he could not master even if he were to pass 20 years in the desert. After the allotted 14 months he can bypass the signifiers for a number of common words and begin to pronounce the signified.
Through all this - the obscured memories, the fighting, the learning, the punishing training in the desert’s stunning heat - he feels a persistent wound in his head. Mostly he is whole, oblivious to any change. Sometimes though, late at night and unable to sleep, early in the morning, or in an unlooked for instant of clarity, he perceives a sprain, a break. An old self and a new self. The old self is half remembered - stunted by pain and drugs, disagreeable, socially inept, irritatingly concerned with adhering to a vaguely conceived and imperfectly reasoned world-view, of which he can now see only a dim and senseless silhouette. These shards of clarity provoke a nostalgia that leaves him sick at the change that has been wrought in him, and his ignorance of it. He tries to clasp his past to him, to return to the older mind-set, but it falls through his fingers. Hands empty, he looks around him at a place where the past ceases to matter, and is forgotten. Gripped by this new self the change in him seems a progression, an evolution ... but when his thoughts open to the fading past he suspects the wound in his head is chemical. His stay at the clinic with the white tiles seems part of some assault by the Company, an assault that required his agreement to commence, and that is now restructuring him from within.