Started playing it quite awhile ago. Put it down for a long period. Picked it up awhile back and finished the Pred campaign, started the Marine one, then put it down and forgot about it again for awhile. Just picked it up again last weekend for some casual play, and a theoretical idea of finishing some games before starting too many new ones. I'm not sure how well I'll do at that after playing some more of it...
There are 3 Campaigns: Aliens, Predators and Marines. The campaign length is in the same order.
Nice graphics, well done sound, animation is fine (though my system started stuttering the second-last time I played, and I couldn't work out if it was the game being badly programmed or my 360 on it's last legs.. not sure. It played fine again this evening. I picked it up 2 copies from Ye Olde Bargain Binne in order to play "Horde Mode" since it looks like fun. Have only managed to play it a couple of times, and the online MP (what little of it there is) is dominated by badly-played Predators.
Predator campaign is probably the best of the three, followed by Aliens as they both at least have some interesting views and modes. Marine one is a bit of a slog. That's the problem with it really. It's not a "sticky" game that makes you want to have One More Go. The Pred and Alien campaigns were playable, and overall decent if not awesome. The Marine one is wildly uneven - Atmosphere in the Marine campaign is great at times, very creepy while many other times it's just whatever in a series of recycled stages set in dark tunnels or jungle foliage. Sometimes it's very well done, other times you just want to get the level over with. The game really does look at it's best and most atmospheric in parts of the Marine campaign where the walls are just totally covered in Giger's biomechanical artwork-cum-game-scenery. When the place you're in looks like the bowels of somewhere out of Alien or Aliens. Overall, the Alien and Pred campaigns actually weren't that bad. The Marine campaign has some good moments - pretty much all as a result of atmosphere and the Art Dept, but gets bogged down in mediocre gameplay.
The shooter mechanics are unfortunately sub-par. At one point I got stuck for 20 or 30 minutes of retrying in a series of back-to-back bullshit fights (aka getting swarmed by waves of aliens in wide open close quarters at night - three times, one after the other). I eventually got through, but sheesh. I just don't have the patience for this kind of crap anymore. And since (I think) I'm playing on Easy, I'm going to blame the game and the console-shooter controls. Though they're far from the best console-shooter controls I've encountered anyway (Borderlands, Calls of Duty are both far better). At this point, I think I'd rather watch both AVP films back to back than play any more of this game.
Chances are I'll still go back and make myself finish it out of bloody-mindedness, though.
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If you're a massive Aliens fan, pick it up on the cheap.
if not, rent or skip it. You won't be missing a whole lot.