When asked how interactive Doom III will be aside from the stuff with the new physics engine, Willits said, "There is equipment that you have to use to move other equipment. The computer systems that you can tap into is very useful. There are NPCs that you have to talk to and work with," Willits wouldn't comment further at this time on how much NPCs in the game would work with the player.

The monsters in Doom III already seem to be a varied bunch, at least according to the screenshots and movies that have already been shown from the game. Willits said of the monsters, "Some demons want to get at you and kill you and other demons are a little more crafty," In terms of new content, Willits said they have some surprises left in terms of new weapons and monsters in addition to some of the favorites from the original Doom games, but adds that players shouldn't expect to see classic Doom levels recreated in Doom III. "You are not going to go, 'Oh, this is E1M5'. That's just not going to happen," he said.