Lin Ye, a 22-year-old delivery boy, witnessed a supernatural battle during a food delivery and accidentally obtained a mysterious "gray coin". This coin cannot directly give him the power to destroy the world, but it allows him to "see and exploit all the loopholes in the world's rules" - ranging from blind spots in the transportation system and gaps in financial data to the price of extraordinary abilities and gaps in ancient contracts. From then on, he wandered on the edge of order and chaos. As a mortal, he circled among chaebols, ancient martial arts families, and secret extraordinary organizations. From a chess piece on the chessboard, he became an "outside the rules" that even the chess players were afraid of.
