Only one of the two games included in the PS4 version of Dead Island Definitive Edition will actually come on the retail disc.
Deep Silver has confirmed that the PS4 SKU includes a Dead Island disc in the box alongside a code to download its sequel Dead Island: Riptide.
This is not the case for Xbox One, where both games can be found on the disc.
As for why this is, Deep Silver initially said on Twitter that PS4 discs don't support multiple games. Clearly this is not the case, of course, owing to former releases such as The Nathan Drake Collection, Borderlands: The Handsome Collection and more notably Deep Silver's own Metro Redux bundle.
Having added that it could've worded that better” in a later tweet, the publisher then told GameSpot: "There are limitations where you are unable to have multiple multiplayer experiences on the same disc, unfortunately we can't comment further."
Dead Island: Definitive Collection will be released at the end of the month.
@GTA_Sammm On XB1 it is on the same disc. PS4 discs don't support multiple games, so there Riptide comes as a download code.— Dead Island (@deadislandgame) May 25, 2016