At last, they reached the chest of the automaton.
A massive gate of polished obsidian brass barred the way, inscribed with equations inlaid in gold—mathematics as prayer, logic as sanctification.
Evangeline touched the sigils, her fingers trembling. "These aren't locks. They're proofs. He requires belief in perfection to enter."
Selene scoffed. "So how do we break it?"
Elric stepped forward, cane in hand, studying the inscriptions. His eyes traced the equations, each line a declaration: All sums are complete. All gears are flawless. All flaws are error.
Slowly, he drew a piece of chalk from his pocket. On the pristine brass, he wrote a single counterproof: 1 ÷ 0 = ?
The gate shuddered.
Evangeline gasped. "You're introducing paradox—"
The equations rippled like disturbed water, lines unraveling, numbers bending in defiance. With a deafening crack, the gate split apart, folding open to reveal the Sanctum within.
It was not a chamber of brass, but of glass. A vast globe of mirrored panels, each reflecting countless possible versions of the Phantom Engineer. He stood at the center, no longer flesh, no longer gear, but a shifting figure of infinite selves.
He turned toward them, his face flickering between man and mask, shadow and flame.
"At last," he said, his voice echoing in all their minds. "The flaw enters the sum."