Heh, what? Doom has always and will always be about opening portals to hell. It's not exactly scarier than other games just because of that. In fact, the Doom games aren't really that scary at all. Doom 3 was just a bunch of monster closets and jump scares interspersed throughout the levels. What little scariness there was wore off within the first few hours.
In fact, I think both Outlast and the original Amnesia were a lot scarier than Doom 3.
