Hasta La Motion!

I wanted to get some feedback/suggestions on how some of you would go about to make this visual effect work.

I need an outline of a person to slide of a rocky wall and begin to walk towards the camera. The image or outline of the person would need to be giving off the reflection or look like the wall it slid off of.

I know this is a vague question and probably more is needed to know in order to answer properly but if you all can start spitting off suggestions that would be cool.

The scene takes place in a mine shaft and there will be very low light conditions.

I was thinking of shooting someone in a chroma key body suit in a studio and then place it into the shot but…just not sure.