Owlcat Games has revealed further details on The Expanse: Osiris Reborn, a third-person shooter and role-playing game due for release in spring 2027 and set in the same period as the first two books of the acclaimed sci-fi series. The developer, best known for top-down RPGs such as Pathfinder: Kingmaker and Warhammer 40,000: Rogue Trader, has drawn inevitable comparisons to Mass Effect thanks to its branching dialogue, choice-driven cutscenes and found-family crew of characters, raising questions about whether it can deliver consequences that feel meaningful rather than cosmetic.

Players take on the role of a spaceship captain navigating relations between three rival factions—Earth, Mars and the Belters—with Owlcat warning that staying on good terms with everyone will require careful decision-making. The studio uses an internal system called Etudes to track player choices, ranging from small cosmetic tweaks to changes that unlock content, kill off characters or alter the ending. A beta released in April drew praise for its combat and visuals but criticism over its story and voice acting, including the absence of the series' distinctive "Belter creole" dialect; Owlcat says it is addressing feedback, including recasting at least one voice actor, ahead of the full launch.