When Luke was still in the maze dungeons and was communicating with them through a projection of his physical body, he had promised to teach Chin, but now that he's here, he has no idea what to teach her.
"What do you want to learn?" he asked.
"How to make cool machines like you," Chin replied.
Luke scratched the back of his neck. 'What do I teach a child?' he thought. He thought of something and nodded. "Alright," he said, "I plan on making a device with these gems," he said taking out the gemstones he removed from the collars.
"What are these?" Chin asked holding one and feeling her magic drain. She dropped it almost immediately.
"Magic canceling gemstones," Luke replied. "It cancels magic from everyone who touches it," he said. "I plan on making bullets with it for a gun but not now," he said.
"So what are we going to make?" Chin asked in curiosity.
"Well... We are going to make cool machines."