Warhammer 40K: Darktide doesn’t have a single-player mode. You can’t play the game solo with bots. It’s designed as a co-op experience, and the developers haven’t included an offline single-player campaign.
Can you play Warhammer 40K: Darktide solo offline?
Unfortunately, there’s no way to play Warhammer 40K: Darktide alone as of writing. There’s no solo mode or single-player content available. The only caveat to this is that bots will fill empty slots in games when no human players are available to join.
Theoretically, you could play Darktide with three bots, making it a single-player experience. However, that option isn’t offered in the game right now. Instead, you must enter matchmaking every time you start the game, and any bot slots can be taken by a player when the match is in progress.
Because you have to matchmake every time, you can’t just cut the internet to your PC to get around the limitations. You’ll immediately be met with an error if you lose connection.
It seems odd that Darktide doesn’t offer some sort of solo mode because Vermintide did. Perhaps one will be added through a future update or an unofficial mod. However, for now, you’re stuck playing with others whether you want to or not.