Doom 3: Resurrection of Evil is the first expansion pack for id Software's popular shooter, Doom 3. For those unfamiliar with the original, it was infamous for its incredible graphics and horror-themed gameplay and this expansion is no different. Despite numerous changes and additions, Resurrection of Evil plays very similarly to its predecessor, so whether or not you enjoyed Doom 3 will ultimately determine if this expansion is for you.

The game's story begins a few years after the events of Doom 3, with a group of marines investigating what appear to be the remnants of an ancient alien civilization, found deep in the caverns of Mars. Evidently, despite the previous disaster, the Union Aerospace Corporation has once again resumed their research on the red planet. The latest team of explorers stumbles across an alien artifact, unexpectedly opening another portal to hell. It isn't long before the entire research base is overrun by demons, once again leaving you as the sole marine alive. Using the artifact's powers, you must fight through legions of enemies to repair the damage and seal the portal to hell once and for all.

At its core, this game is a simple first person shooter. You'll run around shooting anything that moves with an arsenal of powerful weapons. The game's theme, however, mixes things up a bit. Just as in Doom 3, the developers chose to implement horror-themed elements into the expansion. As such, the first thing you'll notice is that the environment itself is extremely dark. Enemies will use this to their advantage, often jumping out of dark corners, coming out of vents, and creeping up from behind. Many of these instances are designed to keep you on the edge of your seat or scare you, and in the early going they do just that. However, as you spend more time with the game, you can begin to predict where the enemy will come from, and that's when the creep factor begins to wear off.

Fortunately, this expansion adds some new features to help vary things a bit. One of the most touted changes is the addition of new weapons, specifically, the grabber gun and the double-barreled shotgun. The grabber gun functions similarly to Half-Life 2's gravity gun, but with one major difference. Its primary use is to fire enemy projectiles back at them, resulting in a powerful blast that will instantly kill most foes. The gun can also interact with small objects in the environment, such as boxes and barrels, which can help you reach hidden areas scattered throughout the game. The double-barreled shotgun pays homage to the same weapon found in Doom 2, and performs nearly the same. Firing consumes two shells, killing most close range enemies with one shot. However, its long reload time can leave you extremely vulnerable to enemy attack.

While Resurrection of Evil's gameplay is fun, it's not without its flaws. The simplistic nature of the action can cause extended sessions of play to become monotonous, so it's better to pace yourself, rather than finish the game in one or two sittings. Also, the alien artifact found at the beginning of the game can become a hindrance over time. As you progress, this artifact empowers you with several new abilities, such as berserk mode and bullet-time, and while these power-ups are interesting, more often that not, you will be saving them for parts that will inevitably require their use. For example, there are a few sequences that require that you use bullet-time to pass an area of booby traps that would otherwise crush you, had they been moving faster. It's this forced nature of the artifact's abilities that makes it feel like a chore to use, and probably should have been omitted altogether.

The single player campaign is pretty short and clocks in somewhere between eight and ten hours. Unfortunately, since the campaign is heavily scripted, there is little reason to play it again, as everything will pan out exactly the same a second time through. The multiplayer component of Resurrection of Evil is also mediocre at best. The multiplayer modes consist of deathmatch, team deathmatch and an all new capture the flag mode. These modes play how you would expect, and there is little else to distinguish them from the already stiff competition. The player limit has also been increased to 8 for the expansion, but that still isn't all that high, as other shooters currently on the market allow for up to 32 or even 64 players. All in all, the multiplayer portion of Resurrection of Evil is definitely the weak point of the game.

Visually, Resurrection of Evil looks superb. To date, the Doom 3 engine is unmatched in terms of technical graphical capability, and it shows. The dynamic lighting, real-time shadowing, high-poly models, and high resolution textures all make for some great eye candy. It's clear that the developers wanted to push the engine even further this time around, so they've varied up the environments to show off more of the engine's capabilities. As you'd expect, they all look phenomenal. There are even some new graphical effects that have been thrown in, such as an x-ray wall that renders everything behind it as if you were looking through x-ray glasses. Unfortunately, in order to experience the graphics at their peak, you will need a powerful processor and a high-end video card. Without them, both performance and quality will suffer, especially later in the game as the environments grow more complex.

The sound is as impressive as the visuals. The ambient noise is the highlight, especially if you have Dolby 5.1 or better surround sound capabilities. You'll hear screams, mechanical noises, and demon-like growls in the distance as you progress through the game's various levels, with all of it sounding great. The infrequent instances of speech from PDAs and other characters in the game are also well done. What little music exists also fits the horror theme for the game quite nicely. As a whole, Resurrection of Evil sounds as a game of this type should, and in combination with the graphics, helps make for a superb audio-visual experience.

Overall, Resurrection of Evil is a fun game, and a worthy expansion to Doom 3. The new gameplay elements help keep the game from getting stale, and the fantastic visuals and audio immerse you in the experience as very few other shooters can. Then again, its hefty price tag and quick single player campaign may scare you away if you're looking for a game with staying power. Ultimately, if you liked Doom 3 and don't mind laying down some extra cash, this expansion pack will provide you with more of the demon shooting action that you know and love.