Operation Darkness is a character-driven, tactical role-playing game, set during World War II. Players lead a team of supernaturally attuned British Special Forces agents on a mission to assassinate Adolf Hitler. Combat is turn-based, different characters have different specialties, and all characters gain experience toward leveling up when victorious in battle. Some team members can use magic to boost their defenses or attack enemies; others can take werewolf form to prevail in melee combat. In addition to Nazi soldiers, the team battles zombies, vampires, and other evil undead, along the way to the ultimate goal of Hitler himself.