F.E.A.R. incorporates the Max Payne/Matrix bullet-time effect so that everything slows down so you can maximize your carnage and shoot 16 guys in the face and still have time to attach a proximity mine on a wall next to the Robocop looking killbot (check the section on "...wave after wave of my own men...") This game has some of the best graphics for a shooter that I've seen. The gore factor extremely high. Close range shotgun blasts make limbs vaporize in a red mist. Wounds profusely bleed and leave hideous smears on the walls and floors. It also makes cool references to Special Forces Operational Detachment - Delta, which is always close to my heart. The story elements are spooky, and it's obvious that the writers gleaned themes from modern Japanese horror films, read "Ringu/The Ring" and "Ju-on/The Grudge."
COD2 is a World War II shooter that has you play through all of the major campaigns of WWII, first as a Soviet rifleman, then as a U.K. armored infantryman, and lastly as a U.S. Army Ranger who supports efforts to make D-Day a success. The play is gritty, not so much in gore, but in the way that battle is portrayed as it should be: messy, confusing, and inaccurate. The American campaign intro sequence pulls from the landing scene in "Saving Private Ryan", and it's just as tough to watch as you're the proponent of the action and the witness to all the destruction. This game is the largest factor in why I haven't posted in so long.
Prey is a beautiful shooter that uses the DOOM3 engine (think portals) and puts you in the shoes of Tommy, a native American who wants to get off the reservation, and end up getting his wish...and so much more. You never run out of lives, rather if you die you're allowed the opportunity to enter the spirit world to recharge your life and spiritual powers before continuing on in your quest. The gameplay is fluid, the graphics are luxurious, the story compelling, and the enemy smacks of the Borg, always a good villain.
Honestly people, aren't these the best villains ever: Borg and Nazis? You just can't get tired of smoking these jokers. Incidentally, name one of the first video games in which a certain German WWII psychopath was THE main boss character. American versions of the game list him as "Master-D", but he looks like you-know-who. Just for the sake of your well-being, know that his head explodes in a very graphic way at the end of the game. It wouldn't be right if it didn't.