Ostracism is a common, yet scarcely studied, phenomenon in the workplace. Thus, it is important to deepen our knowledge of the dynamics of workplace ostracism. Based on the crossover model of the conservation of resources theory (COR), we propose that coworkers ostracize individuals who potentially threaten valued resources in the workplace, namely those that who are mistreated by their supervisors (i.e., abusive supervision). In line with the buffering hypothesis of social support, we also propose that coworker humor is a useful resource to help individuals focus on the silver lining and develop spirals of positivity, reducing the impact of abusive supervision. Data were obtained from employees (abusive supervision, coworker humor, and workplace ostracism) and their respective supervisors (employees' interpersonal deviance) from multiple organizations (N = 518) using previously established scales. Using a boot-strapping method, we found that abusive supervision was positively related to interpersonal deviance via an increase in workplace ostracism, particularly when the use of humor by coworkers was low. This study advances our knowledge of COR theory and its application to workplace ostracism in 3 ways: (a) we examine a crossover model involving all the members of the work unit: individual, supervisor and coworkers; (b) we move beyond the broad buffering hypothesis of social support by testing 1 particular resource, coworker humor; and (c) we offer additional explanations as to why mistreatment often leads to additional mistreatment.