Id Software executive producer Marty Stratton and creative director Hugo Martin revealed to IGN that every mission in Doom contains a classic map from the original two games. All you have to do is find each mission’s hidden lever and pull it. Once activated, a jingle will play and a door will open to a stub of a classic level.
“You get to play them with new guns and new demons, but you’ll notice that in the ones that include demons, they’re actually in the right places,” Stratton said. “We have classic pickups [and] some of the classic music is included in a few of them.”
The classic level revealed in the video is E1M2, and Stratton says once you find a hidden classic map, you unlock the full version of it that can be accessed from the campaign menu.
Doom’s multiplayer beta on PC received some flak for its capped frame rate and lack of other features. Id Software’s CTO, Robert Duffy, addressed the feedback and detailed some of the advanced settings that might appear in the final game.
You can check out Doom gameplay in the links below: