两虎相斗

Explanation: Powerful metaphor of the two-phase fight. 　　Usage: The main predicate; as predicate, object; 　　Source: Han Liu Xiang, "Qin Warring strategy II": "tiger, brutal insect; others, willing to bait. This two Hu Zheng man fighting, while the small die, and large choosing the injury." 　　Examples: This ~, there must be one injury. I have to miss the event. I spake with you two, get off debate. (Ming Luo, "Three Kingdoms" sixty-back)