Gangsta Hat

The Clothier will not list this until the Frost Legion has been beaten, and summoning that event needs a Snow Globe, which only comes out of presents during the Christmas window. On most worlds that locks the hat away for eleven months of the year unless somebody hands you a globe. Once it is unlocked, the shop line only appears after dark on current versions, which catches out players who check at noon and assume the event did not register.

The bowler shape copies the hat that early twentieth century mobsters wear in every film about them. The gangsta snowmen in the event wear an identical one, so what you are putting on is the hat off the enemies you beat to unlock the shop.