this game is crazy. i got this game from gamestop the same time i got lego batman. uh guess which i was playing for the first 2 days until i finished it? yea this game. This game is freaking scary as a mo fo and the ending if you get there is one of the saddest, coolest, and scariest endings i have ever seen in a video game, and ive played all the survival horrors. The way you kill the necromorphs and such a cool inovative way to kill things i was killing them for hours until i was out of ammo. The technique is called dismemberment, and you have to cut off their limbs if you want to kill them. The plasma cutter is the first gun you get, and it can go sideways to shoot off legs, and vertical to cut off arms. It is so cool! For Acheivement wise, if you are a hardcore gamer and will play this game alot in one day, you will get about 600 in that day. I got 645 on my first day so yea. YOu get most from just beating the game and killing bosses through the missionsa and you get achievements for beating missions so its crazy. The plot is one of the best ive seen in a while, and man its good. The beginning hits with a bang and the ending is the best ive seen. There are so many twists in turns in the game u will become dizzy. This game is so crazy and suspensful that you might want to play with a friend haha and that is exactly what i did. I invited a friend over for 2 days so we could finish it, because it was creepy as a mo at night. So if you are like a teen play this with a friend! GREATEST GAME!