Muddy Mittens was born in the soot-stained docks of Gibson, Straya, the son of a Tabaxi barmaid named Golden Tips who labored at The Otter Place. His childhood was defined by the industrial grit of the southern trade hub, where he survived as a rat catcher in the city's labyrinthine slums. Muddy operated under the thumb of Gnordrok, a cruel and bitter half-orc representative of the Exterminator’s Guild, to whom he delivered his daily bounties. His education in the “code of survival” came not from his mother, but from Touch of Frost, a fellow Tabaxi urchin who raised him among the gutters. Despite their meager beginnings, their relationship eventually turned to love; however, this bond was complicated by the revelation that Touch of Frost was the estranged daughter of a wealthy merchant. This forbidden cross-class romance eventually forced Muddy into exile, as the pressure from the city's social elite made his continued presence in Gibson a lethal liability.

The primary motivation for Muddy’s journey across the globe is the search for his father, a Tabaxi who disappeared shortly after Muddy was conceived. The only clue to the man's identity is a fine pocket watch he left behind—a high-quality timepiece gifted to him by the Frumpymelon Docks & Loading Company. Recognizing the company as a titan of industry seated in the Europan capital of Dresden, Muddy dedicated himself to reaching the city to uncover the truth of his lineage. In 2101 A.M., he secured passage aboard the submersible ESS Albacore, joining a disparate group of travelers bound for the Sea of Ghosts. While his initial goals were personal, the violence of the voyage and the subsequent revolution in Europa thrust him into a role he never anticipated: the guardian of a dying captain’s legacy.

Throughout the revolution in Dresden, Muddy carried the physical and emotional weight of a promise made to the late Captain Isaac Carver to deliver the Albacore’s Shardisite Core to the Captain’s family. However, his resolve was profoundly altered during the trek through the Tristessawood, where he was pulled into the realm of the Demon of Sadness. While his companions found clarity through the Archangel Jasiri, Muddy was permanently scarred by the experience; the divine brand on his palm was corrupted and replaced by the Mark of Tristessa. This exposure to demonic energy left him in a state of chronic, internal melancholy, forcing him to navigate the broken streets of Dresden while hiding the physical evidence of his corruption from the rest of the party.