What's the best FPS series of all time in your opinion?

[Veknoid_Outcast]

Half-Life is truly excellent, but there are just too few games.

I have to go with Halo. The first game is, to me, the very best FPS ever made. It JUST edges out Half-Life 2. And then there's Halo 2 and Halo 3, two of the best games of the past ten years. I still haven't played the most recent Halo, but the original trilogy is enough to claim the number one spot.