The Mantis mission is an optional side quest in Starfield that offers players a complimentary set of Legendary armor along with a starship as a reward. However, the challenge lies in the fact that the mission's location remains undisclosed unless players stumble upon an encrypted note. This guide aims to assist space explorers in starting the Mantis side quest, unraveling its perplexing letter puzzle, and swiftly acquiring its loots: The Mantis spacesuit and the Razorleaf ship.