My top 10 list of Pre 2000 FPS
1. Quake III Arena (December 2, 1999)
2. Unreal Tournament (November 30, 1999)
3. Half-Life (November 19, 1998)
4. Team Fortress Classic (7 April, 1999)
5. Starsiege Tribes (November 30, 1998)
6. Doom II (September 30, 1994)
7. Duke Nukem 3D (January 29, 1996)
8. Marathon 2 Durandal (November 24, 1995)
9. System Shock 2 (August 11, 1999)
10 Counterstrike (June 12, 1999)
Honorable Mentions
Goldeneye 007 (August 25, 1997) (I stuck with PC FPS in my list)
Theres also
Rainbow Six, Opposing Force, Thief, Turok, Hexen, Heretic, Blood, Wolfenstien, and Alien vs Predator