Free Wasteland (Wasteland - Trilogy) by Susan Kim, Laurence Klavan

an unnatural and painful angle. His pitiful arms had been lashed together behind his back, and this rope had been tossed over the beam that extended high up the steel pole and then secured. From where he stood, Caleb could see the boy had been beaten. His face was bruised and puffy, and blood dripped from a corner of his mouth.
    But what was most shocking was what the mutants had done to his body.
    The boy had been stripped of most of his clothing, and his pale white skin, long unaccustomed to the burning rays of the sun, had been defaced with obscene drawings smeared in red clay. It took Caleb a moment to realize the boy had been turned into a repellent caricature of a girl, a grotesque and unspeakable travesty. A wig of sorts, made from some filthy and stringy object, sat askew on his head. The smell of wet earth was strong. The scarred and tattooed hands of the mutants were all dark, stained red with mud, and their mouths were open in harsh and mocking laughter.
    The body hanged heavily, twisting a little in the breeze. At first, Caleb thought he must be dead; but when one of the mutants prodded the victim with a metal pipe, the thin sides heaved and the feet kicked feebly.
    “She’s pretty, all right,” said one of the mutants. The rest laughed again, and one of them uttered an obscenity.
    But Caleb no longer heard what they were saying. He was reaching into his backpack, searching for his weapon.
    It was one of a kind. He had forged it over time and through much trial and error. Made of wood, metal, and rubber, it was the length of his forearm and had a crude wheel at the center, held firm on an axis. He kept it loaded: the six rods that fanned out from the wheel were each tipped with a shallow cup that held a jagged rock the size of a hen’s egg. A taut rubber sling kept each rock in place.
    It allowed him to shoot six rocks in as many seconds. He had used it once or twice, on his way to Prin. Now he prepared to employ it again.
    From his hiding place, Caleb took aim at the nearest mutant, who stood facing away. He gave the wheel a sharp spin and as he did, he snapped each sling, firing off three rocks in quick succession. The first two hit the mutant in the head, and the last in the back of the neck. His knees buckled and he slumped to the ground.
    As he calculated, the element of surprise had given Caleb a small but critical advantage. In the confused moment that it took the other mutants to register what had happened, he had time to take aim at his second target. He again set the wheel into swift motion and deployed his last three projectiles. While this mutant raised a hand at the last second to protect himself, it didn’t matter: The rocks came too fast, all three striking his head, and he too was knocked unconscious.
    Caleb was scrambling in his backpack, trying to reload, when one of the remaining mutants spied him through the dense undergrowth. She gave an angry hiss, like an animal. Then she pointed at Caleb, her mouth open in a shriek of fury like a hawk, some bird of prey, and at that, all three mutants rushed the hedge.
    The first one took a running leap and dived headlong through the dense growth at Caleb. At the impact, his weapon flew from his hands and he was knocked backward and onto the hot pavement of the parking lot, the wiry and muscular mutant on top of him, clawing at his throat, his face, trying to subdue him until the others arrived.
    But instead of fighting the momentum, Caleb knew enough to work with it instead. As he curled into a ball and continued to roll backward, he seized the mutant by her scant tunic, pulling in his knees until his feet rested against her stomach. Then he released his grip while violently pushing out with both legs; the mutant was catapulted over his head. A second later, she landed behind him with a sickening crunch.
    As Caleb leaped to his feet, another mutant rushed at him with a rock in an upheld fist. Caleb used his elbow to strike his wrist, loosening his