My favourite shooter franchise is the Metroid series. The reason for my choice is that the storyline captures the mind, the gameplay is outstanding, there are a variety of landscapes and enemies, the weapons are unique and immensely powerful, and the soundtracks of each game contain music masterpieces.

But what shooter franchise would you consider the most revolutionary?

Halo :D

Call of Duty

Metroid isn't no1 because I don't consider it as an FPS franchise.
My favourites are Half-Life for single player and Unreal Tournament (the 1999 edition is one of the games I've played the most in my life) for online and LAN multiplayer (8 players LAN beats easily any other Multiplayer experiences)

I mean any kind of shooter FPS, TPS, etc.
        

I concur, UT is the best multiplayer I've experienced, nothing better than a quick CTF instagib match.

Lan multi on CTF-facing words=esiest way to lose friendships LOL

@Rainbow Yoshi

If you consider all shooter games...I'll go with UT and MP1 on par 1st place, 2nd Half Life

The most influential Shooters were those in my opinion:

-All ID software's games from doom to Quake 2

-Goldeneye 007

-Half-Life

-Quake 3/Unreal Tournament

-Halo (even if I don't like it it was indeed influential)

-Metroid Prime

-Call Of Duty

-Half-Life 2

-Gears Of War

My fav is Half-Life Series By far. I usually dont take FPS seriously but those games have plot ....The best of the series for me is still Half-Life (the first game).Another great shooting game is System Shock 2

I would like to say the Bond series, but it's not true. GoldenEye by itself doesn't make it a great series. :(

I too believe that Metroid is the best and I'm glad that you also consider it a shooter. I get yelled at by people around here for saying that. I'm always corrected and told that it's a first person adventure.

Pretty much anything out of 2K. Prey, The Darkness and the fantastic Bioshock 1 and 2. As far as I'm concerned every other FPS is just the same game with a different cover and setting.