meticulous and unfathomable

"'After Yue Fei's death, the art was lost for half a millennium. Then, during the Ming and Qing Dynasties in Shaanxi Province's Zhongnan Mountains, Yue Fei's boxing manual was discovered by Ji Gong.' Can you imagine trying to learn a martial art from a 500-year-old book?"
"Maybe the guy who found the manual was already expert in some other martial art, and he figured it out by relating it to what he knew."
"Yeah, there's only so many ways to punch a dude. Pretty girl, let's go into the mountains and discover an ancient manual!"
"What if we just pretend to discover an ancient manual?"
"No, actually, let's leave a manual for someone else to discover. We just have to live long enough for someone to discover it."
"We can just fake it so that it looks ancient, and then leave tantalizing hints for would-be discoverers."
"And it'll have moves like Longcat is long."