Quake 4 is a classic first person shooter from 2005.  It is the fourth in a line of games that started with Quake back in 1996.   The graphics have improved immensely. Despite being 7 years old, it’s still a great game and runs on Windows XP and Windows 7.  There are also versions for the Xbox 360, Linux and the Mac.  
The game is set on the planet Stroggos inhabited by a violent cyborg race called the Strogg. Your character’s mission, Marine Corporal Matthew Kane of the fabled Rhino squad, is to land on Stroggos, secure the planet and put an end to Strogg attacks on humans.  During the approach to the planet, Kane’s ship is shot down and separated from the rest of the squads.  He needs to rejoin the force and defeat the Strogg.
Quake 4 has very intense graphics and scenes; there are different kinds of enemies of the Strogg forces on the planet Stroggos and different kinds of drivable vehicles.  The vehicles, tanks and mechanical walkers are fun to drive.  There are a variety of weapons including blasters, machine guns, shotguns, hyperblasters, grenade launchers and nail guns all scattered throughout the levels as well as, ammo, armor and health packs to keep you going.
The most powerful of the Stroggs is the MAKRON, the Strogg leader. The game begins with just one mission to complete on the first level. Other levels have 5 or 6 missions to complete and some levels require you to kill a boss.  Other levels and missions require you to destroy some enemy target.  Of course, the final fight is against the leader of the Strogg, the MAKRON.  He is protecting the nexus core, which you must destroy.  At the end of the game you get a big cliff hanger, but I won’t spoil the surprise.  
This game has very graphic violence, dark shadows, spooky noises, and when you play the game it will keep you on the edge of your seat.  The game has some extreme adult language and it’s meant for an adult audience and not appropriate for children.  
I really liked this game. It is similar to the DOOM games made by the same company, id Software, Raven Software, and Activision.  I think you will really like this game too as much as I have for the last few days.  If you like Quake 4, you will probably also enjoy quake 2 and DOOM 1 and DOOM 2.  For a rating, I would give this game 9.75 of 10 points and I hope you enjoy the game yourself.