Leo returned his attention to the wiring. It was ingenious, definitely, and it made sense to him. This was the motor control relay. This processed sensory input from the eyes. This disk …

“Ha,” he said. “Well, no wonder.”

Creak? the dragon asked with its jaw.

“You’ve got a corroded control disk. Probably regulates your higher reasoning circuits, right? Rusty brain, man. No wonder you’re a little … confused.” He almost said crazy, but he caught himself. “I wish I had a replacement disk, but …this is a complicated piece of circuitry. I’m gonna have to take it out and clean it. Only be a minute.” He pulled out the disk, and the dragon went absolutely still. The glow died in its eyes.

Leo slid off its back and began polishing the disk. He mopped up some oill and Tabasco sauce with his sleeve, which helped cut through the grime, but the more he cleaned, the more concerned he got. Some of the circuits were beyond repair. He could make it better, but not perfect. For that, he’d need a completely new disk, and he had no idea how to build one.

He tried to work quickly. He wasn’t sure how long the dragon’s control disk could be off without damaging it—maybe forever—but he didn’t want to take chances. Once he’d done the best he could, he climbed back up to the dragon’s head and started cleaning the wiring and gearboxes, getting himself filthy in the process.

“Clean hands, dirty equipment,” he muttered, something his mother used to say. By the time he was through, his hands were black with grease and his clothes looked like he’d just lost a mud-wrestling contest, but the mechanisms looked a lot better. He slipped in the disk, connected the last wire, and sparks flew. The dragon shuddered. Its eyes began to glow.

“Better?” Leo asked.

The dragon made a sound like a high-speed drill. It opened its mouth and all its teeth rotated.

“I guess that’s a yes. Hold on, I’ll free you.”

The Lost Hero, Chapter XII