After all of the leaks on Doom, we're getting some official information from the Twitter account of Doom regarding the single-player side of things.
Someone asked how long the single-player campaign would be, with the following reply on the Twitter page for Doom: "The difficulty level plays a factor, but folks playing at the office average 13+ hours in the campaign". Not too bad, but Doom isn't really a single-player game - people will be buying it for the multiplayer (which I think will be short lived, but shhh). As for the single-player side of things, there will be 17 missions. These include:
Doom will be released on May 13 for the Xbox One, PS4 and PC.