Oleg laid sword and whetstone aside. “That is true. But perhaps you are lying. Have you a token? If so, did you eat it? I’ll swear it’s not on you now.”

She didn’t know if she could do it. But she made her voice steady when she said, “I have a sign.”

“Very well. Show me.”

“I will,” she said. “If you tell me why Chelubey said that Dmitrii Ivanovich had devised a novel way to get rid of his cousins.”

Oleg shrugged. “The Prince of Serpukhov is a prisoner here as well. Wasn’t Dmitrii wondering where he had got to?” Oleg paused. “Ah. Messenger, are you? Or a rescue party? Either way it seems unlikely.”

Vasya didn’t reply.

“In any case it was bad planning on Dmitrii’s part,” finished Oleg. “Now Mamai has three of his first cousins.” He crossed his arms. “Now. What is this sign of yours?”

Ignoring her splitting headache, Vasya cupped her hands and filled them with the memory of fire.

Swearing, Oleg scrambled up and back from the fire in her fingers.

She was still kneeling on the floor; she looked up at him through the flames. “Oleg Ivanovich, Mamai is going to lose this war.”

“A ragtag army of Rus’ is going to lose to the Golden Horde?” But Oleg’s voice was thin and breathless; his eyes were on the flames. He reached out to touch, then jerked back at the heat. The fire didn’t hurt her, though she could see the hairs on her arms crisping. “A fine trick,” he said. “Has Dmitrii made alliance with devils? It won’t defeat an army. Do you know how many horses Mamai has? How many arrows, how many men? If every man in Rus’ fought on Dmitrii’s side, he’d still be outnumbered two to one.”

But Oleg did not take his eyes off Vasya’s hands.

Vasya was straining every nerve, through pain, through headache, to keep her face unruffled, to keep steady the memory of fire. Oleg had sided with the enemy to protect his people. A practical man. One she could perhaps reason with. “Tricks with fire?” she said. “Is that what you think? No. Fire and water and darkness all together; the old powers of this land are going to battle alongside the new.” She hoped it was true. “Your general is going to lose. I am the sign of it, and the proof.”

“That Dmitrii Ivanovich has sold his soul for black sorcery?” Oleg made the sign of the cross.

“Is it black sorcery to defend the soil that bore us?” She shut her hands abruptly, extinguishing the flames. “Why did you take me from Chelubey, Oleg Ivanovich?”

“Misplaced kindness,” said Oleg. “Also, I do not like Chelubey.” He reached out a flinching hand to touch her palms, which were quite cool.

“Dmitrii’s side has powers you cannot see,” she said. “We have powers you cannot see. Better to fight for your own, Oleg Ivanovich, than defend a conqueror. Will you help me?”