You will always need an internet connection when playing Diablo 4, but you’ll be able to play solo. We learned this during the deep dive panel on Diablo 4.
Angela Del Priore, the project Lead Designer, responded to a question whether Diablo 4 will get an offline mode, with the following statement:
“We are not going to support an offline mode. But as I said before, nothing in Diablo 4 is going to require partying up. You can play solo and dungeons are private. Campaign quest areas will remain private.”
This won’t come as a shock to people that have played Diablo games before, since this system is the same as in Diablo 3. We think it is important to note that online play doesn’t mean you have to play with other people. You can still do all activities by yourself if you choose to do so.
If you want to learn more about Diablo 4, be sure to read our panel recap.