Clary moved up to stand beside him. The central statue in the fountain, the mermaid, had scales made of overlapping bronze and copper gone green with verdigris. The mermaid held a pitcher, from which water poured, and her face was set in a warrior’s grin.

“Put the blade in the fountain and repeat after me,” said Jace. “Let the waters of this fountain wash this blade clean. Consecrate it to my use alone. Let me use it only in the aid of just causes. Let me wield it in righteousness. Let it guide me to be a worthy warrior of Idris. And let it protect me that I may return to this fountain to bless its metal anew. In Raziel’s name.”

Clary slipped the blade into the water and repeated the words after him. The water rippled and shimmered around the sword, and she was reminded of another fountain, in another place, and Sebastian sitting behind her, looking at the distorted image of her own face. You have a dark heart in you, Valentine’s daughter.

“Good,” Jace said. She felt his hand on her wrist; the water of the fountain splashed up, making his skin cool and wet where it touched hers. He drew back her hand with the sword in it, and released her so that she could lift the blade up. The sun was even farther down now, but there was enough of it to strike sparks off the obsidian stars along the central ridge. “Now give the sword its name.”

“Heosphoros,” she said, sliding it back into its scabbard and tucking the scabbard into her belt. “The dawn-bringer.”

He huffed out a laugh, and bent to feather a kiss against the corner of her mouth. “I should get you home—” He straightened up.

“You’ve been thinking about him,” she said.

“You might have to be more specific,” Jace said, though she suspected he knew what she meant.

“Sebastian,” she said. “I mean, more than usual. And something’s bothering you. What is it?”

“What isn’t?” He started to walk away from her, across the marble floor toward the great double doors of the Hall, which were propped open. She followed him, stepped out onto the wide ledge above the staircase that led down to Angel Square. The sky was darkening to cobalt, the color of sea glass.

“Don’t,” Clary said. “Don’t shut yourself off.”

“I wasn’t going to.” He exhaled harshly. “It just isn’t anything new. Yeah, I think about him. I think about him all the time. I wish I didn’t. I can’t explain it, not to anyone but you, because you were there. It was like I was him, and now, when you tell me things like that he left that box in Amatis’s house, I know exactly why. And I hate that I know it.”

“Jace—”

“Don’t tell me I’m not like him,” he said. “I am. Raised by the same father—we both have the benefits of Valentine’s special education. We speak the same languages. We learned the same style of fighting. We were taught the same morals. Had the same pets. It changed, of course; it all changed when I turned ten, but the foundations of your childhood, they stay with you. Sometimes I wonder if all of this is my fault.”

That jolted Clary. “You can’t be serious. Nothing you did when you were with Sebastian was your choice—”

“I liked it,” he said, and there was a rough undercurrent to his voice, as if the fact rasped at him like sandpaper. “He’s brilliant, Sebastian, but there are holes in his thinking, places where he doesn’t know—I helped him with that. We would sit there and we would talk about how to burn the world down, and it was exciting. I wanted it. Wipe it all clean, start again, a holocaust of fire and blood, and afterward, a shining city on a hill.”

“He made you think you wanted those things,” Clary said, but her voice shook slightly. You have a dark heart in you, Valentine’s daughter. “He made you give him what he wanted.”

“I liked giving it,” said Jace. “Why do you think I could so easily think of ways to break and destroy, but I now can’t think of any way to fix it? I mean, what does that qualify me for, exactly? A job in Hell’s army? I could be a general, like Asmodeus or Sammael.”

“Jace—”

“They were the brightest servants of God, once,” Jace said. “That’s what happens when you fall. Everything that was bright about you becomes dark. As brilliant as you once were, that’s how evil you become. It’s a long way to fall.”

“You haven’t fallen.”

“Not yet,” he said, and then the sky exploded in spangles of red and gold. For a dizzy moment Clary remembered the fireworks that had painted the sky the night they had celebrated in Angel Square. Now she stepped back, trying to get a better view.

But this was no celebration. As her eyes adjusted to the brightness, she saw that the light was the demon towers. Each had lit like a torch, burning red and gold against the sky.

Jace had gone white. “The battle lights,” he said. “We have to get to the Gard.” He reached for her hand and began to tug her down the stairs.

Clary protested. “But my mother. Isabelle, Alec—”

“They’ll all be on their way to the Gard too.” They had reached the foot of the steps. Angel Square was filling with people flinging open the doors of their houses, emptying into the streets, all of them running toward the lighted path that ran up the side of the hill and to the Gard at the top. “That’s what the red-and-gold signal means. ‘Get to the Gard.’ That’s what they’ll expect us to do—” He ducked away from a Shadowhunter who was running past them while strapping on an arm guard. “What’s going on?” Jace shouted after him. “Why the alarm?”

“There’s been another attack!” an older man in worn gear shouted back over his shoulder.

“Another Institute?” Clary called. They were back at a shop-lined street she remembered visiting with Luke before; they were running uphill, but she didn’t feel breathless. Silently she thanked the past few months of training.

The man with the arm guard turned around and jogged uphill backward. “We don’t know yet. The attack’s ongoing.”

He spun back around and redoubled his speed, dashing up the curving street toward the bottom of the Gard path. Clary concentrated on not crashing into anyone in the crowd. They were a moving, jostling flood of people. She kept her hand in Jace’s as they ran, her new sword tapping against the outside of her leg as she went, as if to remind her it was there—there and ready to be used.

The path that led up to the Gard was steep, packed dirt. Clary tried to run carefully—she was wearing boots and jeans, her gear jacket zipped over the top, but it wasn’t quite as good as being all in gear. A pebble had worked its way into her left boot somehow and was stabbing into the pad of her foot by the time they reached the front gate of the Gard and slowed, staring.

The gates were thrown open. Within them was a wide courtyard, grassy in the summers, though it was bare now, surrounded by the interior walls of the Gard. Against one wall was a massive, swirling square of whirling air and emptiness.

A Portal. Within it, Clary thought she could glimpse hints of black and green and burning white, even a patch of sky dotted with stars—

Robert Lightwood loomed up in front of them, blocking their way; Jace nearly crashed into him, and let go of Clary’s hand, righting himself. The wind from the Portal was cold and powerful, blowing through the fabric of Clary’s gear jacket, lifting her hair. “What’s going on?” Jace demanded tersely. “Is this about the London attack? I thought that was rebuffed.”