Suddenly, in one of his far-too-numerous visuals, he saw the first of Plath’s biots. It was hideous, a bug, an attenuated grasshopper, a mite, a tiny monster that loomed six feet tall in the nano subjective. Its face—an insect’s eyes joined by eyes that were an awful parody of Plath’s own eyes. The effect was disturbing and haunting, as if the face he loved had been skinned from her and then blowtorch-melted onto a spider’s face.

“Is that you?” Plath asked him up in the world, but it felt somehow as if it was coming from the biot.

“I guess so,” he said.

“You’re better at this than I am,” she said. “I’ll follow you.”

“I’m coming in behind you two,” Wilkes said.

Keats started to say that no one was better at this, because no one could possibly be good at this. But nevertheless he moved his two biots and dozen nanobots forward.

Like cavalry and infantry, he thought. The nanobots would be the foot soldiers, the pawns, he could lose them. The biots were more precious. They were the king on this chessboard: to lose one was to lose all.

A second Plath biot joined up, and a third, the new one. Keats wondered about its capabilities.

“I may not be able to talk later,” Keats said. “I may …Anyway, I know you don’t want to hear this, but I love you, Sadie.”

Burnofsky cleared his throat.

“I still have the brick,” Wilkes warned him. “So shut up and leave Katniss and Peeta alone.”

Plath should have told him she loved him, too, but those would have just been words. Instead she sent her biots racing forward after his, determined that she would not let him lose this fight.

They reached a rushing, tumbling avalanche of red disks—the blood flowing from the hole in Billy’s cheek. It was a surging flood of licked red cough drops, rolling by like a rocky whitewater river. In with the red disks were spongy white blood cells. And something Keats had never seen before, a kind of thick spiderweb that threw weak and inadequate ropes over the rushing platelets.

“Clotting factor,” Plath said. She was beside him on the pew. He couldn’t see her with the goggles in place. He knew he could move his leg slightly and make physical contact with her, and wanted to, but he worried it might distract her.

They raced along beside the red, red avalanche of blood toward the rim of the volcano that spewed this body-temperature lava.

Keats slowed the pace of his biots and saw that Plath was following suit. The nanobots kept on at full speed.

Ahead, a single blue hydra could be seen atop the crater’s rim, gobbling up passing platelets.

“Mine,” he whispered to Plath.

The front of his first platoon of nanobots hit the single hydra. Six nanobots tore into the hydra and ripped it apart. Hydra legs went flying through the air.

Easy. An easy kill.

“Come on,” Keats said and Plath heard him, of course, and followed him. Twelve nanobots and five biots powered over the crater rim. They were staring down into a witch’s cauldron, a stew of blood cells—red and white, plus clotting factor stretched like fishing nets out from the sides of the hole. The cells spilled steadily over the side, dragging clotting nets with them.

Hydras—an uncountable mass of them—were pushing down through the blood cells, swallowing some, pushing others aside. You couldn’t call it swimming, it looked much more like giant bugs digging their way into soggy gravel.

The main body of hydras was chewing through the deeper epidermal layers, tunneling sideways. They were tunneling beneath the dead outer layer, down through spongy pinkish-gray meat.

Keats faced decision time sooner than he’d hoped. Two groups of hydras heading in different directions. No more platooning. He had to pursue in both directions. Six nanobots, one biot; to Plath, he said, “Stay up there on the rim, catch anything that comes back out. When Wilkes gets here, she comes in behind me.”

“I do. Care,” Plath said.

But Keats didn’t hear it. He let himself go and fell into the pictures in his head. The movements of his fingers would be sequential, one then another, then another, but there was no way, no way in hell to do it unless he lost himself.

Fourteen microscopic creatures to move in two radically different environments.

Don’t think.

K1 and six nanobots dove after the hydras heading down into the blood.

K2 and six nanobots raced after the ones tunneling into the subcutaneous fat of Billy’s face.

Keats heard nothing. He lost awareness of the room he was in. Forgot Plath. Did not feel the hard pew under his thighs. Was not thirsty or hungry. His heart did not beat, he did not breathe, not so that he noticed, anyway.

Once before, when he had been tested, all the way back in London, he had gone away like this, lost himself in the game, felt nothing, ceased to exist as a consciousness.

Within the red gravel a hydra leg. One of Keats’s nanobots clawed it and reeled the hydra in. The others swarmed over the first and over the shredded hydra using both as a ladder, fighting the surge and pause, surge and pause of the red avalanche.

Seven different views of platelets and lymphocytes and clotting fibers. Seven sets of arms and legs, all swarming, all searching, catching a second hydra, ripping it apart, another and stabbing it, and another and another, catching up to a massed body of the replicated hydras, weak, shambling disjointed creatures built with only one ability: to build more of themselves.

The hydras did not fight, they were not controlled, they were as simple and mindless as mites, no one in charge; they were on automatic. They didn’t fight, they didn’t flee, they just gobbled up flesh and shit out carbon while the MightyMites did their sub-visible work, building more, ever more hydras.