Eragon wondered how many Urgals he could kill at once with magic. He knew his limits fairly well. If he were to kill enough to make a difference . . . it would probably be suicide. That might be what it took to win.

The fighting continued for one endless hour after another. The Varden and dwarves were exhausted, but the Urgals remained fresh with reinforcements.

It was a nightmare for Eragon. Though he and Saphira fought their hardest, there was always another Urgal to take the place of the one just killed. His whole body hurt—especially his head. Every time he used magic he lost a little more energy. Saphira was in better condition, though her wings were punctured with small wounds.

As he parried a blow, the Twins contacted him urgently.There are loud noises under Tronjheim. It sounds like Urgals are trying to dig into the city! We need you and Arya to collapse any tunnels they’re excavating.

Eragon dispatched his opponent with a sword thrust.We’ll be right there. He looked for Arya and saw her engaged with a knot of struggling Urgals. Saphira quickly forged a path to the elf, leaving a pile of crumpled bodies in her wake. Eragon extended his hand and said, “Get on!”

Arya jumped onto Saphira’s back without hesitation. She wrapped her right arm around Eragon’s waist, wielding her bloodstained sword with the other. As Saphira crouched to take off, an Urgal ran at her, howling, then lifted an ax and smashed her in the chest.

Saphira roared with pain and lurched forward, feet leaving the ground. Her wings snapped open, straining to keep them from crashing as she veered wildly to one side, right wingtip scraping the ground. Below them, the Urgal pulled back his arm to throw the ax. But Arya raised her palm, shouting, and an emerald ball of energy shot from her hand, killing the Urgal. With a colossal heave of her shoulders, Saphira righted herself, barely making it over the heads of the warriors. She pulled away from the battlefield with powerful wing strokes and rasping breath.

Are you all right?asked Eragon, concerned. He could not see where she had been struck.

I’ll live,she said grimly,but the front of my armor has been crushed together.It hurts my chest, and I’m having trouble moving.

Can you get us to the dragonhold?

. . . We’ll see.

Eragon explained Saphira’s condition to Arya. “I’ll stay and help Saphira when we land,” she offered. “Once she is free of the armor, I will join you.”

“Thank you,” he said. The flight was laborious for Saphira; she glided whenever she could. When they reached the dragonhold, she dropped heavily to Isidar Mithrim, where the Twins were supposed to be watching the battle, but it was empty. Eragon jumped to the floor and winced as he saw the damage the Urgal had done. Four of the metal plates on Saphira’s chest had been hammered together, restricting her ability to bend and breathe. “Stay well,” he said, putting a hand on her side, then ran out the archway.

He stopped and swore. He was at the top of Vol Turin, The Endless Staircase. Because of his worry for Saphira, he had not considered how he would get to Tronjheim’s base—where the Urgals were breaking in. There was no time to climb down. He looked at the narrow trough to the right of the stairs, then grabbed one of the leather pads and threw himself down on it.

The stone slide was smooth as lacquered wood. With the leather underneath him, he accelerated almost instantly to a frightening speed, the walls blurring and the curve of the slide pressing him high against the wall. Eragon lay completely flat so he would go faster. The air rushed past his helm, making it vibrate like a weather vane in a gale. The trough was too confined for him, and he was perilously close to flying out, but as long as he kept his arms and legs still, he was safe.

It was a swift descent, but it still took him nearly ten minutes to reach the bottom. The slide leveled out at the end and sent him skidding halfway across the huge carnelian floor.

When he finally came to a stop, he was too dizzy to walk. His first attempt to stand made him nauseated, so he curled up, head in his hands, and waited for things to stop spinning. When he felt better, he stood and warily looked around.

The great chamber was completely deserted, the silence unsettling. Rosy light filtered down from Isidar Mithrim. He faltered—Where was he supposed to go?—and cast out his mind for the Twins. Nothing. He froze as loud knocking echoed through Tronjheim.

An explosion split the air. A long slab of the chamber floor buckled and blew thirty feet up. Needles of rocks flew outward as it crashed down. Eragon stumbled back, stunned, groping for Zar’roc. The twisted shapes of Urgals clambered out of the hole in the floor.

Eragon hesitated. Should he flee? Or should he stay and try to close the tunnel? Even if he managed to seal it before the Urgals attacked him, what if Tronjheim was already breached elsewhere? He could not find all the places in time to prevent the city-mountain from being captured.But if I run to one of Tronjheim’s gates and blast it open, the Varden could retake Tronjheim without having to siege it. Before he could decide, a tall man garbed entirely in black armor emerged from the tunnel and looked directly at him.

It was Durza.

The Shade carried his pale blade marked with the scratch from Ajihad. A black roundshield with a crimson ensign rested on his arm. His dark helmet was richly decorated, like a general’s, and a long snakeskin cloak billowed around him. Madness burned in his maroon eyes, the madness of one who enjoys power and finds himself in the position to use it.

Eragon knew he was neither fast enough nor strong enough to escape the fiend before him. He immediately warned Saphira, though he knew it was impossible for her to rescue him. He dropped into a crouch and quickly reviewed what Brom had told him about fighting another magic user. It was not encouraging. And Ajihad had said that Shades could only be destroyed by a thrust through the heart.