Clary felt tiny daggers of ice shoot through her veins; she tried to keep her face from showing any expression as the woman kneeling by the throne rose. It was indeed Amatis, with her disconcerting Luke-blue eyes. She smiled. “With pleasure,” she said, and stalked out of the room, the hem of her long red coat sweeping behind her.

Jace stepped forward with an inarticulate growl—and stopped in his tracks, several feet from Sebastian. He put his hands out, but they seemed to collide with something translucent, an invisible wall.

Sebastian snorted. “As if I’d let you get near me—you, with that fire burning in you. Once was enough, thank you.”

“So you know I can kill you,” Jace said, facing him, and Clary couldn’t help but think how alike they were and how different—like ice and fire, Sebastian all white and black, and Jace burning up with red and gold. “You can’t hide in there forever. You’ll starve.”

Sebastian made a quick gesture with his fingers, the way Clary had seen Magnus gesture when casting a spell—and Jace flew up and back, and slammed into the wall behind them. Her breath caught in a gasp as she spun to see him crumple to the ground, a bloody gash across the side of his head.

Sebastian hummed in delight and lowered his hand. “Don’t worry,” he said conversationally, and turned his gaze back to Clary. “He’ll be fine. Eventually. If I don’t change my mind about what to do with him. I’m sure you understand, now that you’ve seen what I can do.”

Clary held herself still. She knew how important it was to keep her face blank, not to look at Jace in panic, not to show Sebastian her anger or her fear. Deep down in her heart she knew what he wanted, better than anyone else; she knew what he was like, and that was the best weapon she had.

Well, maybe the second-best.

“I’ve always known you had power,” she said, deliberately not looking toward Jace, deliberately not analyzing his motionlessness, the thick trickle of blood that was making its way down the side of his face. This was always going to happen; it was always going to be her facing Sebastian with no one else, not even Jace, by her side.

“Power,” he echoed, as if it were an insult. “Is that what you call it? Here I have more than power, Clary. Here in this keep I can shape what is real.” He had begun to pace inside the circle he had drawn, his hands looped casually behind his back, like a professor delivering a lecture. “This world is connected only by the thinnest threads to the one where we were born. The road through Faerie is one such thread. These windows are another. Step through that one”—he pointed to the window on the right, through which Clary could see dark blue twilight sky, and stars—“and you will return to Idris. But it’s not that simple.” He regarded the stars through the window. “I came to this world because it was a place to hide. And then I began to realize. I am sure our father quoted these words to you many times”—he spoke to Jace, as if Jace could hear him—“but it is better to rule in Hell than serve in Heaven. And here I rule. I have my Dark Ones and my demons. I have my keep and citadel. And when the borders of this world are sealed, everything here will be my weapon. Rocks, dead trees, the ground itself will come to my hand and wield its power for me. And the Great Ones, the old demons, will look down on my work, and they will reward me. They will raise me up in glory, and I will rule the abysses between worlds and the spaces between all the stars.”

“‘And he shall rule them with a rod of iron,’” said Clary, remembering Alec’s words in the Accords Hall, “‘and I will give him the Morning Star.’”

Sebastian whirled on her, his eyes bright. “Yes!” he said. “Yes, very good, you’re understanding now. I thought I wanted our world, to bring it down in blood, but I want more than that. I want the legacy of the Morgenstern name.”

“You want to be the devil?” Clary said, half-baffled and half-terrified. “You want to rule Hell?” She spread her hands out. “Go ahead, then,” she said. “None of us will stop you. Let us go home, promise you’ll leave our world alone, and you can have Hell.”

“Alas,” said Sebastian. “For I have discovered one other thing that perhaps sets me apart from Lucifer. I do not want to rule alone.” He extended his arm, an elegant gesture, and indicated the two great thrones on the dais. “One of those is for me. And the other—the other is for you.”

The streets of Alicante turned and twisted back in on themselves like the currents of a sea; if Emma hadn’t been following Helen, who was carrying a witchlight in one hand and her crossbow in the other, she would have been hopelessly lost.

The last of the sun was vanishing from the sky, and the streets were dark. Julian was carrying Tavvy, the baby’s arms locked around his neck; Emma held Dru by the hand, and the twins clung together in silence.

Dru wasn’t fast, and kept stumbling; she fell several times, and Emma had to drag her to her feet. Jules called out to Emma to be careful, and she was trying to be careful. She couldn’t imagine how Julian did it, holding Tavvy so carefully, murmuring so reassuringly that the little boy didn’t even cry. Dru was sobbing silently; Emma brushed the tears off the younger girl’s cheeks as she helped her up for the fourth time, murmuring nonsense comforting words the way her mother once had to her when she’d been a child and had fallen.

She had never missed her parents more agonizingly than she did now; it felt like a knife under her ribs.

“Dru,” she began, and then the sky lit up red. The demon towers had flamed to the color of pure scarlet, all the gold of warning gone.

“The city walls are broken,” Helen said, staring up at the Gard. Emma knew she was thinking about Aline. The red glow of the towers turned her pale hair the color of blood. “Come on—quickly.”

Emma wasn’t sure they could go any more quickly; she got a tighter hold of Drusilla’s wrist and yanked the little girl nearly off her feet, muttering apologies as she went. The twins, hand in hand, were faster, even as they raced up a jagged set of stairs toward Angel Square, led by Helen.

They were almost at the top step when Julian gasped out, “Helen, behind us!” and Emma spun around to see a faerie knight in white armor approaching the foot of the stairs. He carried a bow made from a curved branch, and his hair was long and bark-colored.

For a moment his eyes met Helen’s. The expression on his face changed, and Emma couldn’t help wondering if he recognized the Fair Folk in her blood—and then Helen raised her right arm and shot her crossbow directly at him.

He whirled away. The bolt hit the wall behind him. The faerie smirked, and leaped up the first step, then the second—and screamed. Emma watched in shock as his legs buckled under him; he fell and howled as his skin came into contact with the edge of the step. For the first time Emma noticed that corkscrews, nails, and other hunks of cold-forged iron had been hammered into the step edges. The faerie warrior reeled back, and Helen shot again. The bolt went through his armor and into his chest. He crumpled.

“They’ve faerie-proofed,” Emma said, remembering looking out the window at the Penhallows’ with Ty and Helen. “All the metal, the iron.” She pointed at a nearby building, where a long row of scissors hung from cords connected to the edge of the roof. “That’s what the guards were doing—”