The maze branched off into two different paths. Call picked the left one at random and headed down it. His heart was beating hard and his throat felt like it was burning from the superheated air he was inhaling. At least there was no smoke.

Fire wants to burn. He remembered his own ironic retort to that the first time he’d heard the Cinquain. Call wants to live. At that moment, the flames burned down lower and Call was able to look out across the maze.

He saw no one. His heart sped up as he realized not one single other student was visible. He seemed to be alone in the labyrinth, though he could still see the Masters standing against the walls.

“Aaron?” he called. “Tamara?”

He strained his ears to hear above the snapping of the fire. He thought he caught his name, faint as a whisper. He lunged toward the sound, just as the flames shot up around him again, now burning as high as telephone poles. Nearly caught by a blast of rising fire, Call staggered free, the edge of one of his sleeves burning. He put it out with a slap, but his eyes were stinging, almost blinded, and he was coughing hard.

He reached for his canteen and thumbed it open, expecting to see the familiar glint of water. Water that he could draw on, whose power he could use to douse the flame.

But it was empty.

Call shook it right next to his ear, hoping he was wrong, hoping for the familiar slosh of liquid. He tipped it over against his hand, hoping for even a single drop. There wasn’t. There was nothing, except a tiny hole in the base. It looked as though it had been drilled through.

“Master Rufus!” he shouted. “My canteen doesn’t have any water! You have to stop the test!”

But the flames only leaped up around him. A blast of it shot out in his direction and he had to jump to one side to avoid it. Call stumbled and went down hard on one knee, only narrowly avoiding face-planting into a wall of fire. Pain raced up his side. For a moment when he stood up, he wasn’t sure if his bad leg was going to hold him.

“Master Rufus!” he yelled again. “Master North! Someone!”

Why did he think it would be okay to be on his own? Why had he trusted the Masters to keep him safe? If Tamara or Aaron were with him, he could have borrowed some of their water! But then his thoughts veered abruptly: What if neither Tamara’s nor Aaron’s canteen had water? What if the same person who’d targeted him wanted to make sure they couldn’t have helped, no matter what.

He had to find them.

Call started walking again, trying to ignore the growing heat all around him. Balls of fire worked their way loose at intervals and flew in random directions, like flares. He dodged one as he made his way around a corner. He turned another and found himself standing in front of a wall of fire.

He’d come to a dead end.

Skidding to a halt, he turned around, ready to retrace his steps, only to find a wall there, too. The maze had changed and the fire all around him seemed to be reaching out with tongues of flame, singeing him, making the air stink with burned hair and burned cloth.

Call’s anguished howl was swallowed up by the fire. Of course the maze changed. Otherwise, there was barely any need for the water — there had to be places where magic was required.

Just then one of the walls shifted closer. Call could see the metal rivets on his boots glowing orange red. Unless he wanted to be barbecued, Call had to find a way out of the maze. He couldn’t fly up; Tamara was right, it would be even hotter in the air right above the flames.

Air. Wait, Call thought. Fire needs air, right? Fire feeds on air.

He had an idea.

He thrust out his left hand, the way he’d seen the mages do when they were summoning power into their spells. The way he’d seen Aaron do it. He reached out, farther than the fire around him, farther than the stone under his feet. Farther than the water running in the brooks and creeks miles above them. Farther than the air. He reached through space that existed and didn’t, reaching past it into nothingness. Into the heart of the void.

The heat of the fire faded away. He could no longer feel his skin burning and prickling. In fact, he was cold. Cold as outer space, where there was no warmth, only nothingness. In the center of his palm, a black spiral began to dance. It rose up and up from his skin like a coil of smoke set free.

Fire wants to burn.

Air wants to rise.

Water wants to flow.

Earth wants to bind.

Chaos wants to devour.

The chaos rose up from Call’s hand, faster and faster now. It had become a black tornado, spinning around his wrist and hand. He could feel it, thick and oily, like quicksand that would pull you under. He thrust his hand up higher, as high as it could go, until he was reaching toward the top of the flames.

Devour, he thought. Devour the air.

The smoke exploded outward. Call gasped as a noise like a sonic boom punctured the air. The flames began to sway wildly back and forth as the black smoke ran across their tops, spreading like a cloud layer, devouring oxygen. Fire needed oxygen to live. Call had learned that in science class. His dark chaos was eating away at the oxygen surrounding the flames.

He could hear other noises now: other apprentices, shouting in surprise and fear. The flames made a noise as if they were being turned inside out — then vanished, collapsing down to heaps of charred ash. Suddenly, the whole room was visible — Call could see the other students spread out across the floor, some of them clutching their canteens, all of them looking around wildly in shock.

Call’s smoke was still hovering in the air. Dark and sinuous, it appeared to have fattened up on the air it had swallowed. Call started to gasp, remembering something else he knew from science class: Fire might need oxygen to survive, but so did people.

The smoke began to drift down, questing, coiling. Master Rufus was striding toward the destroyed maze, shouting, “Call! Get rid of it, Call!”

In a panic, Call flung his hand out again, reaching for the chaos, trying to pull it back toward him. He felt it resist. It wanted to push back and be free. It wanted him to leave it alone. He was stretching out his hand so hard his fingers were turning into aching claws. Come back.

Suddenly, the dark chaos smoke swirled into a tight coil and sprang toward the ground. Call gave a yell — then saw that it was arrowing down toward Aaron, whose hand was also raised. It vanished into his palm and disappeared.

Master Rufus skidded to a stop a few feet from Call. Aaron slowly lowered his hand. Call could see Tamara, her cheeks streaked with ash, her mouth open. Across the heaps of ash and the huddles of frightened students, Call and Aaron looked at each other.