In January 2020, an American base was attacked by the largest theater ballistic missile strike in history. This case report covers the resulting mass casualty (MASCAL) incident. In this case, we defined this incident as a MASCAL due to a lack of medical personnel available to properly and timely evaluate the patients. There was no loss of life during the attack but there were > 80 traumatic brain injuries (TBIs). This article focuses on lessons learned from diagnosing and treating Soldiers during a TBI MASCAL event.