Aiko Kimura had fed the dark gold bird four charges, and four times she had watched it die. She stood inside the glass conservatory, its dome throwing pale light across her workbench. The little bird lay on the back of her hand, wings folded, cold. She wanted it to wake. Not to fly a route or carry a message like the others she built, but to choose. To open its eyes and stay. She had built birds for years, ever since she watched a courier pigeon freeze mid-flight, its message lost for three weeks. This one was different. This one she wanted alive. She touched the winding key at its breast and turned. A spark ran through the tiny gears. For a breath, the bird trembled. Then a thin curl of smoke rose from its chest. The charge burned straight through and died. Aiko set it down and pressed her fists to the bench. The core was wrong. Her wire was too coarse. Every spark she fed it tore through the metal before a soul could catch. "You've scorched it again," a voice said behind her. Cho Cogsmith stood in the conservatory doorway, goggles pushed up in his black hair, trinkets clinking as he crossed to her. He ran the curiosity shop across the way, and he had been her friend long enough to walk in uninvited. "Smells like burnt clock oil in here. Aiko, what are you trying to do, cook the poor thing?" "Hold a spark," she said. "Long enough for it to wake. But the core can't take it." Cho leaned close and studied the smoking bird. His grin faded into something quieter. He reached into his coat and drew out a strange gadget, half a thing, missing a piece he had never named. "I bought this off a seller who swore it came as a pair," he said. "Never knew what it did." He pried open its casing. Inside coiled a thread of wire, finer than any Aiko owned, wound tight as spider silk. "This isn't the piece I needed. But maybe it's the piece you need." Aiko took the wire. It bent without breaking, thin enough to cradle a charge instead of burning under it. Her hands moved fast. She stripped the ruined core from the bird's chest and threaded the fine wire in its place, coiling it around the smallest gear. Then she turned the key. The spark ran in. This time it did not burn. It held, glowing steady in the bird's breast. The wings twitched. One eye opened, then the other, a bright bead of dark gold. The bird lifted its head and looked at her. "It held," Cho breathed. Aiko didn't move. The bird stood on her hand, awake, watching her. But it had not chosen yet. It cocked its head toward the vast glass panes and the open sky beyond, and its wings began to stir.