Clary paled under the dirt on her face. “We thought he’d be with you.”
 
Alec shook his head. “He’s all right,” he said. “I’d know if he weren’t—”
 
But Clary had already spun back around and was half-running back the way she’d come; after a moment Alec followed her, and so did the others. She scrambled up the rise, and then up another rise. Alec realized she was heading for higher ground, where the view would be better. He could hear her coughing; his own lungs felt coated with ash.
 
Dead, he thought. Everything in this world is dead and burned to dust. What happened here?
 
At the top of the hill was a cairn of stones—a circle of smooth rocks, like a dried-out well. Seated on the edge of the cairn was Jace, staring at the ground.
 
“Jace!” Clary skidded to a halt in front of him, dropped to her knees, and caught at his shoulders. He looked at her blankly. “Jace,” she said again, urgently. “Jace, snap out of it. It’s not real. It’s a demon, making us see the things we want. Alec killed it. Okay? It’s not real.”
 
“I know.” He looked up, and Alec felt the look like a blow. Jace looked as if he’d been bleeding out, though he was obviously uninjured.
 
“What did you see?” Alec said. “Max?”
 
Jace shook his head. “I didn’t see anything.”
 
“It’s all right, whatever you saw. It’s all right,” Clary said. She leaned in, touched Jace’s face; Alec was reminded acutely of Magnus’s fingers on his cheek in the dream. Magnus saying he loved him. Magnus, who might not even still be alive. “I saw Sebastian,” she said. “I was in Idris. The Fairchild house was still standing. My mom was with Luke. I—there was going to be a wedding.” She swallowed. “I had a little sister, too. She was named after Valentine. He was a hero. Sebastian was there but he was fine, he was normal. He loved me. Like a real brother.”
 
“That’s messed up,” Simon said. He moved closer to Isabelle, and they stood shoulder to shoulder. Jace reached out and ran a careful finger down one of Clary’s curls, letting it wind around his hand. Alec remembered the first time he’d realized Jace was in love with her: He’d been watching his parabatai across a room, watching Jace’s eyes track her movements. He remembered thinking: She’s all he sees.
 
“We all have dreams,” Clary said. “It doesn’t mean anything. Remember what I said before? We stay together.”
 
Jace kissed her forehead and stood up, holding out a hand; after a moment Clary took it, and rose to her feet beside him. “I didn’t see anything,” he said gently. “All right?”
 
She hesitated, clearly not believing him; just as clearly, she didn’t want to press the point. “All right.”
 
“I hate to bring this up,” Isabelle said, “but did anyone see a way back?”
 
Alec thought of his headlong rush over the desert hills, searching for the others, eyes raking the horizon. He saw his companions pale as they glanced around. “I think,” he said, “that there is no way back. Not from here, not down the tunnel. I think it closed up after us.”
 
“So this was a one-way trip,” said Clary, with only a slight tremble to her voice.
 
“Not necessarily,” said Simon. “We have to get to Sebastian—we always knew that. And once we get there, Jace can try to do his thing with the heavenly fire, whatever that is—no offense—”
 
“None taken,” said Jace, casting his eyes up to the sky.
 
“And once we rescue the prisoners,” said Alec, “Magnus can help us get back. Or we can figure out how Sebastian gets back and forth; this can’t be the only way.”
 
“That’s optimistic,” said Isabelle. “What if we can’t rescue the prisoners, or we can’t kill Sebastian?”
 
“Then he’ll kill us,” said Jace. “And it won’t matter that we don’t know how to get back.”
 
Clary squared her small shoulders. “Then we’d better get to finding him, hadn’t we?”
 
Jace tugged his stele free of his pocket, and took Sebastian’s bracelet off his wrist. He closed his fingers around it, using the stele to draw a tracking rune on the back of his hand. A moment passed, and then another; a look of intense concentration passed over Jace’s face, like a cloud. He lifted his head.
 
“He’s not that far,” he said. “A day, maybe two days of walking away.” He slid the bracelet back onto his wrist. Alec looked at it pointedly, and then at Jace. If I cannot reach Heaven, I will raise Hell.
 
“Wearing it will keep me from losing it,” Jace said, and when Alec said nothing, Jace shrugged and started off down the hill. “We should get moving,” he called back over his shoulder. “We’ve got a long way to go.”
 
 
 
 
 15
 BRIMSTONE AND SALT
 
 
 
“Please don’t rip my hand off,” Magnus said. “I like that hand. I need that hand.”
 
“Hmph,” said Raphael, who was kneeling beside him, his hands on the chain that ran between the manacle on Magnus’s right hand and the adamas loop sunk deep into the floor. “I am only trying to help.” He jerked, hard, on the chain, and Magnus yelped in pain and glared. Raphael had thin, boyish hands, but that was deceptive: He had a vampire’s strength, and he was currently bending its power to the purpose of yanking Magnus’s chains out by the roots.
 
The cell they were in was circular. The floor was made of granite flagstones, overlapping. Stone benches ran around the inside of the walls. There was no discernible door, though there were narrow windows—as narrow as arrow slits. There was no glass in them, and it was possible to see from their depth that the walls were at least a foot thick.
 
Magnus had woken up in this room, a circle of red-geared Dark Shadowhunters standing around him, affixing his chains to the floor. Before the door had clanged shut behind them, he’d seen Sebastian standing in the corridor outside, grinning in at him like a death’s-head.
 
Now Luke stood at one of the windows, staring out. None of them had been given a change of clothes, and he still wore the suit trousers and shirt he’d worn to dinner in Alicante. The front of his shirt was splashed with rusty stains. Magnus had to keep reminding himself it was wine. Luke looked haggard, his hair rumpled, one of the lenses of his glasses cracked.
 
“Do you see anything?” Magnus asked now, as Raphael moved to his other side to see if the left-hand chain would be any easier to remove. Magnus was the only one chained. By the time he’d woken up, Luke and Raphael had already been awake, Raphael lounging against one of the benches while Luke called out for Jocelyn until he was hoarse.
 
“No,” Luke said shortly. Raphael raised an eyebrow at Magnus. He looked tousled and young, teeth digging into his lower lip as his knuckles whitened around the chain links. They were long enough to allow Magnus to sit up, but not to stand. “Just fog. Gray-yellow fog. Maybe mountains in the distance. It’s hard to tell.”
 
“Do you think we’re still in Idris?” Raphael asked.
 
“No,” Magnus said shortly. “We’re not in Idris. I can feel it in my blood.”
 
Luke looked at him. “Where are we?”
 
Magnus could feel the burn in his blood, the beginning of fever. It prickled along his nerves, drying his mouth, making his throat ache. “We’re in Edom,” he said. “A demon dimension.”
 
Raphael dropped the chain and swore in Spanish. “I cannot free you,” he said, clearly frustrated. “Why have Sebastian’s servants chained only you and not either of us?”
 
“Because Magnus needs his hands to do magic,” said Luke.
 
Raphael looked at Magnus, surprised. Magnus wiggled his eyebrows. “Didn’t know that, vampire?” he said. “I would have thought you would have figured it out by now; you’ve been alive long enough.”
 
“Perhaps.” Raphael sat back on his heels. “But I have never had much business with warlocks.”
 
Magnus gave him a look, a look that said: We both know that isn’t true. Raphael looked away.
 
“Too bad,” Magnus said. “If Sebastian had done his research, he would have known I can’t do magic in this realm. There’s no need for this.” He rattled his chains like Marley’s ghost.
 
“So this is where Sebastian’s been hiding all this time,” Luke said. “This is why we couldn’t track him. This is his base of operations.”
 
“Or,” said Raphael, “this is just some place he has abandoned us to die and rot.”
 
“He wouldn’t bother,” Luke said. “If he wanted us dead, we’d be dead, the three of us. He’s got some larger plan. He always does. I just don’t know why—” He broke off, looking down at his hands, and Magnus remembered him suddenly much younger, flyaway hair and worried looks and his heart on his sleeve.
 
“He won’t hurt her,” Magnus said. “Jocelyn, I mean.”
 
“He might,” Raphael said. “He is very crazy.”
 
“Why wouldn’t he hurt her?” Luke sounded as if he were holding in a fear that threatened to explode. “Because she’s his mother? It doesn’t work that way. Sebastian doesn’t work that way.”
 
“Not because she’s his mother,” Magnus said. “Because she’s Clary’s mother. She’s leverage. And he won’t give that up easily.”
 
   
 
 
 
They had been walking for what seemed like hours now, and Clary was exhausted.
 
The uneven ground made the walking harder. None of the hills were very high, but they were pathless, and covered in shale and jagged rock. Sometimes there were plains of sticky, tarry pitch to cross, and their feet sank in almost to the ankles, dragging down their steps.
 
They paused to put on runes for sure-footedness and strength, and to drink water. It was a dry place, all smoke and ashes, with the occasional bright river of molten rock sludging through the burned land. Their faces were already smeared with dirt and ash, their gear powdered with it.
 
“Ration the water,” Alec warned, capping his plastic bottle. They had paused in the shadow of a small mountain. Its jagged top snarled up into peaks and crenellations that made it resemble a crown. “We don’t know how long we’ll be traveling.”
 
Jace touched the bracelet on his wrist, and then his tracking rune. He frowned at the traced pattern on the back of his hand. “The runes we just put on,” he said. “Someone show me one.”
 
Isabelle made an impatient noise, then thrust out her wrist, where Alec had inked a speed rune earlier. She blinked down at it. “It’s fading,” she said, a sudden uncertainty in her voice.
 
“My tracking rune as well, and the others,” said Jace, glancing over his skin. “I think runes fade more quickly here. We’re going to have to be careful about using them. Check to make sure when they need to be applied again.”
 
“Our Speed runes are fading,” Isabelle said, sounding frustrated. “That could be the difference between two days of walking and three. Sebastian could be doing anything to the prisoners.”
 
Alec winced.
 
“He won’t,” Jace said. “They’re his insurance that the Clave will turn us over to him. He won’t do anything to them unless he’s sure that won’t happen.”
 
“We could walk all night,” Isabelle said. “We could use Wakefulness runes. Keep applying them.”
 
Jace glanced around. Dirt was smudged under his eyes, and across his cheeks and forehead where he’d rubbed the palm of his hand. The sky had deepened from yellow to dark orange, smeared with roiling black clouds. Clary guessed that meant that nightfall was near. She wondered if days and nights were the same in this place, or if the hours were different, the rotations of this planet subtly misaligned.
 
“When Wakefulness runes fade, you crash,” Jace said. “Then we’ll be facing Sebastian basically hungover—not a good idea.”
 
Alec followed Jace’s gaze around the deadly landscape. “Then we’re going to have to find a place to rest. Sleep. Aren’t we?”
 
Clary didn’t hear whatever Jace said next. She’d already moved away from the conversation, clambering up the steep side of a ridge of rock. The effort made her cough; the air was foul, thick with smoke and ash, but she didn’t feel like staying for an argument. She was exhausted, her head was pounding, and she kept seeing her mother, over and over, in her head. Her mother and Luke, standing on a balcony together, hand in hand, looking down at her fondly.
 
She dragged herself up to the top of the rise and paused there. It sloped down steeply on the other side, ending in a plateau of gray rock that stretched to the horizon, piled here and there with heaps of slag and shale. The sun had lowered in the sky, though it was still the same burned orange color.
 
“What are you looking at?” said a voice at her elbow; she started, and turned to find Simon there. He wasn’t quite as grimy as the rest of them—dirt never seemed to stick to vampires—but his hair was full of dust.
 
She pointed to dark holes where they pocked the side of the nearby hill like gunshot wounds. “Those are cave entrances, I think,” she said.
 
“Kind of looks like something out of World of Warcraft, doesn’t it?” he said, gesturing around them at the blasted landscape, the ash-torn sky. “Only, you can’t just turn it off to get away.”
 
“I haven’t been able to turn it off for a long time.” Clary could see Jace and the other Lightwoods a distance away, still arguing.
 
“Are you all right?” Simon asked. “I haven’t had a chance to talk to you since everything happened with your mother, and Luke—”
 
“No,” Clary said. “I’m not all right. But I have to keep going. If I keep going, I can not think about it.”
 
“I’m sorry.” Simon put his hands into his pockets, his head down. His brown hair blew across his forehead, across the place where the Mark of Cain had been.
 
“Are you kidding? I’m the one who’s sorry. For everything. The fact that you got turned into a vampire, the Mark of Cain—”
 
“That protected me,” Simon protested. “That was a miracle. It was something only you could do.”
 
“That’s what I’m afraid of,” Clary whispered.
 
“What?”
 
“That I don’t have any more miracles in me,” she said, and pressed her lips together as the others joined them, Jace looking curiously from Simon to Clary as if wondering what they had been talking about.
 
Isabelle gazed out over the plain, at the acres of bleakness ahead, the view choked with dust. “Did you see something?”
 
“What about those caves?” Simon asked, gesturing toward the dark entrances tunneling into the mountainside. “They’re shelter—”
 
“Good idea,” Jace said. “We’re in a demon dimension, God knows what lives here, and you want to crawl into a narrow dark hole and—”
 
“All right,” Simon interrupted. “It was just a suggestion. You don’t need to get pissed off—”
 
Jace, who was clearly in a mood, gave him a cold look. “That wasn’t me pissed off, vampire—”
 
A dark piece of cloud detached itself from the sky and darted suddenly downward, faster than any of them could follow. Clary caught a single horrible glimpse of wings and teeth and dozens of red eyes, and then Jace was rising up into the air, caught in the clawed grip of an airborne demon.
 
Isabelle screamed. Clary’s hand went to her belt, but the demon had already shot back up into the sky, a whirl of leathery wings, emitting a high-pitched squeal of victory. Jace made no noise at all; Clary could see his boots dangling, motionless. Was he dead?
 
Her vision went white. Clary whirled on Alec, who already had his bow out, an arrow notched and ready.
 
“Shoot it!” she screamed.
 
He spun like a dancer, scanning the sky. “I can’t get a clear shot; it’s too dark—I could hit Jace—”
 
Isabelle’s whip uncoiled from her hand, a glimmering wire, reaching up, up, impossibly up. Its shimmering light illuminated the clouded sky, and Clary heard the demon scream again, this time a shrill cry of pain. The creature was spinning through the air, tumbling over and over, Jace caught in its grip. Its claws were sunk deep into his back—or was he clinging to it? Clary thought she saw the gleam of a seraph blade, or it might only have been the shimmer of Izzy’s whip as it reached up, and then fell back to earth in a brightening coil.
 
Alec swore, and let an arrow fly. It shot upward, piercing the darkness; a second later a heaving dark mass plummeted to earth and hit the ground with a whump that sent up a cloud of powdery ash.
 
They all stared. Splayed, the demon was large, almost the size of a horse, with a dark green, turtle-like body; limp, leathery wings; six centipede-like clawed appendages; and a long stem of a neck that ended in a circle of eyes and jagged, uneven teeth. The shaft of Alec’s arrow protruded from its side.
 
Jace was kneeling on its back, a seraph blade in his hand. He plunged it down into the back of the creature’s neck viciously, over and over, sending up small geysers of black ichor that sprayed his clothes and face. The demon gave a squealing gurgle and slumped, its multiple red eyes going blank and lightless.
 
Jace slid from its back, breathing hard. The seraph blade had already begun to warp and twist with ichor; he tossed it to the side and looked levelly at the small group of his friends, all staring at him with expressions of astonishment.
 
“That,” he said, “was me pissed off.”
 
Alec made a sound halfway between a groan and an expletive, and lowered his bow. His black hair was stuck to his forehead with sweat.
 
“You don’t all have to look so worried,” Jace said. “I was doing fine.”
 
Clary, light-headed with relief, gasped. “Fine? If your definition of ‘fine’ suddenly includes becoming a snack for a flying death turtle, then we are going to have to have words, Jace Lightwood—”
 
“It didn’t vanish,” Simon interrupted, looking as stunned as the rest of them. “The demon. It didn’t vanish when you killed it.”
 
“No, it didn’t,” Isabelle said. “Which means its home dimension is here.” Her head was craned back, and she was studying the sky. Clary could see the gleam of a newly applied Farsighted rune on her neck. “And apparently these demons can go out in the daylight. Probably because the sun here is almost burnt out. We need to get out of this area.”
 
Simon coughed loudly. “What were you all saying about taking shelter in the caves being a bad idea?”
 
“Actually, that was just Jace,” said Alec. “Seems like a fine idea to me.”
 
Jace glared at them both, and scrubbed a hand across his face, succeeding in smearing the black ichor across his cheek. “Let’s check the caves out. We’ll find a small one, scout it thoroughly before we rest. I’ll take first watch.”
 
Alec nodded and started to move toward the nearest cave entrance. The rest of them followed; Clary fell into step beside Jace. He was silent, lost in thought; under the heavy cloud cover, his hair glinted a dull gold, and she could see the massive rips in the back of his gear jacket where the demon’s claws had taken hold. The corner of his mouth quirked up suddenly.
 
“What?” Clary demanded. “Is something funny?”
 
“ ‘Flying death turtle’?” he said. “Only you.”
 
“ ‘Only me’? Is that good or bad?” she asked as they reached the cave entrance, looming up before them like an open, dark mouth.
 
Even in the shadows his smile was quicksilver. “It’s perfect.”