I just finished Resurrection of Evil, the expansion pack to Doom 3. I found it pretty entertaining, but not in the same way as the original Doom 3. Doom 3 was really scary. The expansion just really wasn't. It used a lot of graphics and sounds from the original game, and added more along the same lines, but it just wasn't scary. I don't think it's a problem of being "more of the same," because Doom 3 is pretty long, and by the end, it's still scary. I think it's more that Nerve (the company that made the expansion) just expected that if they made more levels for Doom 3, they'd be scary too. I don't know... the expansion levels just weren't as suspenseful, as creepy, or as unnerving as the original Doom 3 missions. It's still a good game (extremely hard in many parts), but it didn't have the same magic for me that the original did.
There were a couple bugs, too... in one level you have to pace yourself and kill zombies at a particular interval so you can take their life support packs. It's similar to the outdoor sections where you have to periodically pick up air tanks, except this was prolonged and difficult, including a miniboss battle. The bug is that if your life support runs out for even a second, and then you pick up a new pack, you get stuck at something like -39 points of life support, so you eventually suffocate. You have to make sure that you pick up another tank before you hit 0. I couldn't ever manage it, so I had to switch on god mode for that part. The final battle was just too hard also, so I turned on god mode for that too. Maybe I should have picked a lower difficulty level. Anyway... if you thought that the original was too hard, then don't bother with the expansion, or pick an easier difficulty level.
The new content is pretty cool. Despite what you might have heard, the bugged section of the game I mentioned earlier is the only part where you get a forehead-mounted flashlight. With that exception, it's just like the original, which will be bad for most of you, but I rather liked having to switch between flashlight and weapon. The double-barreled shotgun is incredibly powerful, but you only get one shot every few seconds, so make sure you aim well. The Artifact, though, is the focus of the expansion. Since there's no Soulcube (or "Time Cube," as I preferred to call it) in the expansion, you get your evil alien technology in the form of this pulsating heart. You can hold it out as you run over human corpses and it will steal their souls, disintegrating the body in the process. You can expend a soul to activate it. Each time you complete a boss battle you get a new power for the artifact. What I didn't know from the reviews is that you get all of the powers at once when you activate it. So, if you've ever thought to yourself, "man, I wish this game had a weapon that would give me super speed, slow time like in Max Payne, quadruple (!) my damage, and make me invulnerable, all at once," then Resurrection of Evil is your game. The fact that the game is still hard even with the Artifact is noteworthy. In retrospect, I probably could have used the Artifact more than I did, because there are souls everywhere with which to replenish it. The designers were considerate enough to include piles of human corpses around the arena for all of the boss battles, so you can use the Artifact pretty much as much as you want. Except... the last one. I only found one or two corpses for the final battle versus (it would only be a spoiler if you never finished the original) the Betruger-dragon-thingy, which is why it was so hard.
The gravity gun (yes, it has a gravity gun) is interesting. In some ways it's easier to use than the one in Half-Life 2, and in others, it's more difficult. One thing's for certain, though; the Doom 3 version looks much, much cooler. It's necessary for one of the boss battles. Some of the demons' own projectiles do a ton of damage when thrown back at them, so it's the best way to get rid of a cacodemon (the big floating heads that spew plasma, not the little floating heads that charge you). You can also pick up the little floating heads and throw them into the ground, pick up spiders and throw them at other spiders, and pick up babies and throw them across the room.
If you loved Doom 3 as much as I did, you'll probably still like Resurrection of Evil quite a bit. I enjoyed myself. But, still, it's kind of annoying how much better the original was. I think that what I think of the expansion is similar to what other people thought of the original: just another fast-paced action game with dark corridors and loud noises and blinking lights. But, hey, if it's going to be that, at least it's a fun one.
Oh yeah, and there aren't very many locker codes in this one either.