A good shooter for anyone with a budget in mind. It's dated, but its also a blast.
HIGH POINTS: Premise. It seems a little standard with its "aliens attacking Earth" plot, but it ends up keeping you entertained at least enough to finish the game. The way the premise is incorporated into the gameplay are what really suck you in. All of the guns, even though they are variations of typical FPS standards, are well developed and are given a decidedly "alien" look. Also, the gravity-defying walk walking sections and the portal puzzle really add a unique and exhilarating experience that cannot be found elsewhere. If you like "Portal", you will definitely enough the portals in this game. Finally, I feel that the music is worth noting. It is very 'heroic' and inspiring, and sounds like a soundtrack out of a summer action flick. There is some pretty decent licensed music to be found in sections of the game as well.
LOW POINTS: First, graphics. This game is old. Like, launch title old. So don't expect to be blown away by this aspect of the game. Next, there are some sections of the game that start to drag. The environments can look really similar, and you feel like you are doing the same thing over and over. There isn't a lot of repetition with the enemies you face either. You have basically seen every chump you'll have to face about half way through the game. Finally, the difficulty is on the easy side. Not because the game doesn't have challenging sections, because it does. However, it is impossible to die, at least in the traditional sense. Mind you, I actually found this to be an interesting addition to the typical formula, but it didn't change the fact that you are basically not penalized for death. When you lose all of your health, you are transported to a "Spirit Land". All you do here is shoot wraiths until you are transported to your exact spot of death. This made you more willing to take chances and experiment, but also lent the game to simply taking the 'Rambo' approach and powering through tough parts.
FINAL SCOOP: Overall, this game is not perfect. Far from it. But for the price, it is a fun and engaging shooter that is well worth the money and time that you will invest into it. A good addition to any FPS-fan's library. Looking for a game to compare this too? Think Doom 3. This game definitely has a very similar overall feel. So if you liked Doom 3 (as I did), you will more than likely enjoy this.