On the mutation awakening day, Lu Li was reborn and returned, only to find that his beast was a 'chaos beast' that could only eat fragments of rules. He was sacrificed in his previous life, but in this life he decided to use loopholes in the rules to rewrite his destiny. In the National Games Beast Control Bureau, the useless director Bai Ye seemed lazy, but secretly handed him a "Complete of Rules and Loopholes"; doctor Su Mei stared at his blood, and instructor Tieshan tested his bottom line with his fists again and again. When Qin Mo stole the 'Rules Contract' from the archives, Lu Li discovered that the fate of all beastmasters was controlled by a hidden rule - and only he could see the loopholes in this rule. He wants to gain a foothold in the Beast Taming Bureau, to unravel the cause of death in his previous life, and to make those superior beast masters understand that rules are meant to be broken. Although the Chaos Beast is weak, it can swallow up the rules and grow. When Lu Li used the 'rule loophole' to counter-kill high-level beasts for the first time, the entire beast-control bureau exploded. But the real crisis has just begun - Su Mei's sister's resurrection experiment went out of control, Bai Ye's true identity surfaced, and the organization behind Qin Mo was waiting for Lu Li to tear open the door with his own hands. This time, he is no longer the sacrificed chess piece, but the chess player.