Objective: Serious games are potentially powerful tools for residency training and increasingly attract attention from medical educators. At present, serious games have little evidence-based relations with competency-based medical education, which may impede their incorporation into residency training programs. The aim of this study was to identify highly valued entrustable professional activities (EPAs) to support designers in the development of new, serious games built on a valid needs-assessment. Materials and Methods: All 149 licensed medical specialists from seven specialties in one academic hospital participated in seven different Delphi expert panels. They filled out a two-round Delphi survey, aimed at identifying the most valuable EPAs in their respective curricula. Specialists were asked to name the most highly valued EPA in their area in the first Delphi round. In the second round, the generated responses were presented and ranked according to priority by the medical specialists. Results: Sixty-two EPAs were identified as valuable training subjects throughout five specialties. Eleven EPAs - "management of trauma patient," "chest tube placement," "laparoscopic cholecystectomy," "assessment of vital signs," "airway management," "induction of general anesthesia," "assessment of suicidal patient," "psychiatric assessment," "gastroscopy," "colonoscopy," and "resuscitation of emergency patients" - were consistently given a high score. Conclusions: The future medical specialist is an active learner, comfortable with digital techniques and learning strategies such as serious gaming. In order to maximize the impact and acceptance of new serious games, it is vital to select the most relevant training subjects. Although some serious games have already targeted top-priority EPAs, plenty of opportunities remain.