Back 4 Blood is an always-online game, developer Turtle Rock has confirmed.

It means the upcoming Left 4 Dead spiritual successor cannot be played offline, even solo with AI teammates.

"We're looking into ways we could support offline for the future but you will need an internet connection to play at launch," Turtle Rock tweeted in response to a question on the subject.

"There is zero, and I mean ZERO reason why we shouldn't be able to play this game offline.

If you can do it with Left 4 Dead, you can do it with this game too.".

Back 4 Blood is the latest game to insist on an internet connection even when played solo, and the news has sparked concern it may be unplayable if server trouble blights launch.

That's what happened with the recently-released Outriders, which requires an internet connection even when played solo.

And then there's the game preservation issue that comes with an always-online game.

Eventually, Back 4 Blood's servers will switch off, and without an offline mode, the game will be dead.

It's worth noting Turtle Rock said it's looking into offline play, so maybe it will turn up at some point.

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