The demon flies straight at me, like an arrow fired from a bow. A scream builds at the back of my throat, but before it can burst out of my mouth, the Kallin hits an invisible barrier and is deflected. It crashes into a group of other long, hairy demons. Irritated, their fangs flash and they rip the first Kallin to shreds. Bloody bits of it fly everywhere.

I press myself hard against Raz as the demons surround us, gnashing at the barrier, wriggling around and over it, searching for weak points. Within seconds, they cover the barrier entirely, blocking our view of the sky, plunging us into almost total darkness. I can see by the light of the pulsing patches, but the others must be nearly blind.

Nadia clicks her fingers and a ball of flame appears overhead. I preferred the darkness. We can see the Kallin in more detail now, their long, hairy bodies, the stiff, spiky hairs on which they move, their abnormally large mouths and fangs. They drool and slobber as they snake across the face of the barrier. Soon it's like looking at them through a window streaked with spit and vile juices.

Raz is sweating. So are Sharmila and Nadia. Trembling, not with fear, but the effort of maintaining the barrier. This is hard. I don't think they can keep it up for more than a few minutes. I glance at Beranabus and the window he's working on. It's nowhere near complete. A few minutes won't be long enough.

One of the Kallin penetrates the barrier with its head. It squeals with triumph, fangs snapping together, trying to squeeze the rest of its body through. I tense, readying myself to fight, but then Nadia shouts a brief spell and the barrier closes sharply around the demon, slicing its head off.

The head falls to the floor, but the jaws continue snapping open and shut. It drags itself forward using its fangs, dozens of eyes glittering angrily. I get to my knees, face the head, try summoning magic to use against it. Instead, panic-stricken, I throw up. The demon gibbers - it can still make noise - and crawls at me through the pool of vomit. I watch, repulsed and terrified. Then, as it's about to drag itself out of the vomitous pool, I have a thought. I reach out, touch the vomit with a finger and charge it with magic, which flows through me from some unknown source.

The vomit bubbles and becomes acid. The Kallin head shakes wildly. Desperate, it hurls itself out of the pool, using an upper fang as a makeshift vaulting pole. I make a fist and, roaring with fear, punch the head back down. The acid eats into it. The head shakes a few more times, then dissolves, bubbling away to a bloody, hair-streaked mess.

A feeling of power and victory washes through me. I've killed a demon! I used magic to destroy its ugly ass! I'm Hercules, Samson and Thor rolled into one! I glare at the thousands of Kallin, eager for another to break through, so I can send it the way of its boiled-down brother. "Come on," I snarl. "I'll turn you all into stew!"

"The boy's enjoying himself," Raz notes, teeth chattering from the effort of keeping the barrier in place.

"I do not think he will be so... anxious to fight... when the barrier breaks... and they come crashing down upon us... in their multitudes," Sharmila mumbles.

Nadia says nothing. She's staring ahead, eyes wide open now, sweat filling the pockmarks on her face. Terrified.

Overcome with confidence, forgetting that moments ago I was throwing up and more afraid than I'd ever been, I take matters into my own hands. Turning to where Beranabus is piecing together a window, I watch the pulsing lights for a couple of seconds. Then, impatient, I reach up and nudge a patch of light towards the cluster. It slides ahead of my fingers, slotting into place. I start moving others. It's simple. I don't even have to touch the lights - they move before my fingers, weightless, a breeze to manipulate.

"What are you doing?" Beranabus snaps.

"I can do it quicker than you," I tell him, adding more patches of light to the now rapidly forming window.

"You're distracting me," Beranabus growls. "Get out of my way before - "

"You're too slow!" I shout. "You can't see the lights. I can. So let me do it. I can make..." I pause. The lights around me have stopped pulsing. For a second - absolute panic. I can't complete the window! Then I realise what's happened. "Where were you trying to open the window to?" I pant. Beranabus starts to argue. "Just tell me!" I yell.

Beranabus squints then says, "I was searching for Cadaver."

I think about the demon which stole my brother. Recall its long legs, stumpy body, thick hairy fingers. Its face, half human, half canine. Its drooping ears and wide white eyes.

The patches of light start pulsing again. Eagerly, I reach up and begin slotting them into place, creating a window. I'm not sure how or why this works, but I know I'm right. I was never crazy. The lights weren't imaginary. They were there for a reason - and now that reason is clear. I can't use magic to make sandcastles or barriers, but I can sure as hell open windows to other worlds!

Beranabus stares at me wordlessly. He can't see the lights. He only sees my hands moving swiftly, fingers flying in all directions, like a mad conductor. But he feels the magic. He knows -  hopes - I'm not blowing our only chance of survival.

"Master!" Raz shouts.

"Hush," Beranabus says. "Let him work. If he can do what I think..."

"But the barrier!" Raz cries. "We cannot hold it! I feel it crumbling!"

Beranabus mutters a quick spell and I sense the barrier thicken around us. The cries of the demons and howl of the wind are muted slightly.

"Relax," Beranabus says to me. "I can hold this barrier for a long while now that I have nothing else to focus on. You have time."

I don't respond or slow down. Too excited. I can see the window coming together. For the first time in my life I feel completely in control of myself and the world around me. I have a purpose. I know what I was born for. This is my gift. Why I always felt like a misfit. I had a great power. A destiny.

"What's he doing?" Nadia asks.

"Something I've never seen anyone else do," Beranabus says softly. "Not even the most powerful demon master."

"Are you sure he is not having some kind of fit?" Sharmila asks.

"We're dead if he is," Beranabus laughs.

"I don't like this, master," Raz says. "To place our lives in the hands of an untested child..."

"Children are often the true saviours," Beranabus says. "Not knowing the rules of the universes, they can sometimes turn those rules on their head. We must trust, Raz Warlo. And hope." I feel his eyes hot on my back. "The boy is all we have."

I don't think about my grave responsibility. All I focus on are the patches of light, pulsing in the air around me, more gliding into reach from the world outside, slipping through the ranks of Kallin and the wall of the barrier. Nothing can hold the lights back, interfere with them or divert them from their course. Except me. I'm their master. I can do anything with them that I like.

My hands blur. The panel of lights builds, two feet wide, three feet high... four... five. Just as I'm adding a large, hexagonal block of blue light to the mass, the lights pulse in unison a few times, then go a dull shade of steady white.

"By all the gods!" Raz gasps.

"I do not believe it!" Sharmila exclaims.

"No!" Nadia moans with disbelief.

Beranabus just chuckles and says, "My compliments, Kennel."

"It's Kernel," I correct him, looking up at his bearded face and small dark eyes. "Kernel Fleck. Master of the lights."

He tilts his head, acknowledging my power. I've never felt more alive or special. The others gawp from me to the window, then back at me.

"How?" Nadia asks.

Beranabus speaks before I can. "Let's save the explanations for when we're not surrounded by thousands of demons." He stares at the writhing ranks of the Kallin. Smiles. Then steps through the window of light. I glance at the others, grinning proudly. They're smiling too now.

One last look at the Kallin. They're screeching louder than ever, furious at us for escaping their trap. Laughing, I flip them the finger, then face the window of light and eagerly step forward after Beranabus, figuring nowhere in the universe can be as bad as this place.

Wrong!