Doom was a game with a story, a fright factor, crazy amounts of bad guys, cool-assed weapons of mass monster killing. Without Doom we wouldn’t have had a Quake, a Half-life or a Halo. Well, we may have had those games, but they wouldn’t have been the same. Id’s little creation changed how gaming was looked at, and there really hasn’t been a hugely innovative concept in the FPS genre since. All we’ve done is modify the original. And it’s all good.