Mimir is a recurring character in the God of War video game series, serving as an advisor and source of knowledge for the protagonist, Kratos. Known as the 'Smartest Man Alive,' Mimir is originally a figure from Norse mythology. In the series, he is depicted as a disembodied head with deep wisdom of the Nine Realms, providing guidance, historical context, and comic relief to Kratos and his son Atreus during their journey.