This game was very successful at the time of it release .......... gorgeous graphics and does not require a graphics card to play it!!.
The best FPS(First person shooter) game ever........ there's some great pumping action and serious fragging that will blow you away it is still considered one of the best games.
Weapons,level of detail,gestures,some special powers like quad damage,regeneration,invisibility etc etc ,stages are simply awesome ....... you better play it now!!

And those who have played it please share your experience!! and tell me on which difficulty you play i.e.
1.) xxx
2.) xxx
3.) Hurt me Plenty
4.) Hardcore
5.) Nightmare

above mentioned difficulties which are xxx are for toddlers