Mr. Sun's Hatbox is a roguelite platformer where players build a team of reformed hat thieves to retrieve a stolen hatbox. The game begins with a solo delivery squad that expands into an organization of criminals. Players can recruit or defeat Mr. Moon's minions and utilize over 50 unique hats, each granting special properties. Missions range from wave-based action to espionage, culminating in Hat Heists where collecting crowns unlocks crew perks.The game supports solo, co-op, and PvP modes, including local co-op and 1v1 or last-man-standing PvP battles. Players can upgrade their base of operations, adding facilities like a Brig, Lab, and Black Market. Character quirks, such as nearsightedness or quick reflexes, influence mission suitability. Mr. Sun's Hatbox features a distinct pixel art style by Kenny Sun, creator of *Circa Infinity* and *Yankai's Peak*.