Items earned in MultiVersus' Battle Pass won't be exclusive as there "may be opportunities to unlock some of these items in the game at a later date".
Battle passes have quickly become the norm in free-to-play titles and there are a few rules that they all tend to follow. One of these rules is that items earned within the pass are usually exclusive to that pass and don't pop up at a later date, including unique skins, taunts, and more. MultiVersus has confirmed that it won't be following this trend, and that items included within the Battle Pass may be made available to unlock through other means.
After having entered its open beta phase, the MultiVersus website was updated to include an F&Q exclusive to information about the open beta. This section of the site includes some information on the content included with the Battle Pass, and reveals that some of its contents might be made available to earn at a later date.
The question asks whether the contents of a Battle Pass are exclusive, and the site reveals, "Items earned from a MultiVersus Battle Pass are not exclusive. There may be opportunities to unlock some of these items in the game at a later date".
It's not confirmed which items within the Battle Pass might be made unlockable in the future, but it seems likely that it's referring to some of the bigger bits of content like taunts and skins. It seems likely that the content will simply be made available for purchase through the in-game store, and not unlockable through gameplay, as the same section of the site confirms that Gleamium is the only way to earn character variants.
Although Battle Pass content apparently isn't exclusive, that doesn't mean that all of MultiVersus' content will always be unlockable. The game currently has a few Summer-themed costumes for purchase outside of the Battle Pass, including Coach Steven and Beach Iron Giant, which will all be available throughout Summer, seemingly going away after that. Whether they'll be brought back at a later date isn't clear, but it seems like there will be a few timed exclusives.
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