One of a finger-ful of first-person-shooters that actually tries something new, 'Aliens Vs Predator' is fantastic for as long as it lasts, which  unfortunately isn't all that long. Splitting the game into Marine, Alien  and Predator phases ensures great variety, but you feel that you're playing  three short games instead of one long one. Still, it's worth the price for  the Alien segments alone. Whilst the Marine stages are superior shoot-em-up  action with an extremely scary atmosphere, and the Predator section seems  oddly detatched (we never learn enough about the creature in the films to  care much, although the execution of his multiple vision modes is superb),  the Alien sections could be a game in themselves. Treating ceilings and  walls as if they were floors, as the Alien you have to keep yourself  hidden, and restrict your combat to quick darts from the shadows. The  feeling of power, as you cling to a roof high above your blinded,  blundering victim-to-be, is addictive, and soon you'll be disappointed that  people don't scream in horror when you approach them in real life.