Costly manipulation to gain selective admission exhibits strategic complementarity when the admissions quota is loose but strategic substitution when the quota is tight. In a system with two layers of selection, gaming at the university entrance stage can induce a university to give preferential treatment to students from a selective high school, justifying why this school attracts better talent and causing gaming to unravel to the high school entrance stage. We apply this framework to evaluate the impacts of raising the university quota, abolishing university entrance examinations, eliminating sorting-by-ability in the high school system, and committing to low-powered selection policies.