Ok, I've heard of a couple of stories recently and I have heard several versions of this one story. So I've put the pieces together and this is what I got.Chan Yu, a Chinese 11 year old who lived in China hundreds of years ago. He lived close to the tomb of the first emperor. He spent most of his time near and around it. One day he was being chased by a dog. (The Animal is different in most of the stories) He tried losing it around some tree's, but it continued it's chase. So he went to his haven, the tomb. Chan reached the Tomb within minutes. The Dog kept up it's chase. When the ground shook around them. The dog turned tail and ran the other way; while Chan fell to the ground. Suddenly the ground gave way, and Chan fell into a cavern.Chan had fallen into the tomb of the first emperor. He found no way out, and spent his years inside the tomb. He learned to consentrate, and learn. By sitting and thinking. One day something changed. He meditated (same as the animal one, constantly changes) and then he felt everything become lighter, his soul had left his body.He spent the last years of his life exploring the hidden rooms in the tomb, and exploring the outside world. One day his soul flew into the river of mercury. His mercury clung to his soul and draged him down to the bottem of the river. His soul was stuck on the river bed. His body decayed and but his soul lived on the riverbed.He eventually learnt how to swim in the mercury. He swam out of the river, but soon relized that he could not leave the tomb, he needed to stay near his skeleton, or blow away as a whisper in the wind.This is a shortened version, though this story does make sense. Since the tales of the first emperor's tomb is that there is a 'River of flowing Mercury', and that there are 'Guardians of the tomb'.