D2 already did that, every map must have had tens of hundreds of monsters. Where d1 didn't have as many monsters, it still was much better in terms of creating that doomed atmosphere. What killed the doomed atmosphere in both games was the ability to play online, because it killed the storyline by making some parts of it avoidable. I think the atmosphere of diablo does add to the doomed feeling, but dimembered bodies, sacrificial areas, and bizzare evil occurances gets old and borring fast. Without the proper amount of contrast between good and evil the game won't create as much of a doomed atmosphere. Instead it will create a predictable world environment with very little concept behind it. The sudden shift between peace and war, or the concept of knowing that destruction is imminent, are far better methods of instilling "Doom" on a character than scary images. An MMO could easily create a doomed feeling, but ultimately it is up to the player to buy it. For example, WoW could create this doomed atmosphere simply by having the burning legion invade again. Sure this would be their 10th try, but I have to admit that I would probably piss my pants if some demon king came trotting across my lawn. My point is that an MMO could create a better sense of doom than both d1 and d2 combined. Whether or not it will is up to the developers, but I am sure they have something up their sleeve.