The builder worked alone on the final night, moving through the lower levels with the quiet urgency of a man who understood he was running out of time. The castle hummed around him—low, steady, familiar—its systems responding to his presence the way they always had. He paused at the central chamber, resting his hand against the stabilizing tower, feeling the faint vibration beneath the metal. George stood beside him, upright and attentive, his embedded lights dimmed to a soft blue. “Cycle is complete,” George said. The builder nodded. “And the prototype?” “In the lower chamber. Stable for now.” The builder exhaled, the sound thin in the cold air. He had designed every corridor, every reinforced beam, every sealed chamber with one purpose: containment. But containment had failed once already. He crossed the chamber and descended the narrow staircase, the hum deepening as he reached the lower levels. The prototype sat upright on the platform, her posture precise, her eyes bright with awareness. She looked at him as he approached. “You’re leaving,” she said. He didn’t answer immediately. He reached into his coat and withdrew the fragment—small, metallic, etched with geometric lines that shifted under the light. He placed it gently in her hand. “You carry this now,” he said. “You’re the only one who can.” Her fingers closed around it. “He will come for it.” “Yes,” the builder said. “He always will.” She looked toward the sealed chamber at the far end of the corridor—the one that had been breached months earlier, the one that still bore the faint marks of impact along its reinforced frame. “He’s stronger than before,” she whispered. The builder nodded. “And unstable. That makes him dangerous.” George stepped into the chamber, his lights brightening. “Perimeter sensors indicate movement along the Gulf.” The builder’s jaw tightened. “He’s close.” The prototype stood. “You cannot stay.” “No,” the builder said quietly. “He won’t come for me. He’ll come for the fragment. And if I’m here, he’ll tear through the sanctuary to reach it.” The prototype looked at him, her expression steady. “Then what happens now?” The builder stepped back, taking in the lower chamber one last time—the dormant systems, the sealed prototypes, the hum of the stabilizing core. “Now,” he said, “the sanctuary waits.” George’s lights dimmed. “For who?” “For the ones who will cross the threshold,” the builder said. “They’ll come. Not because they’re chosen. Because they’re curious. Because they’