bzflag can also be played in CTF mode. In this type of game there are two (or more) teams of up to four tanks a team. The objective is to grab your opponents flag by running over it and then bringing it back to your base. Each team has a base which is basicly a square of the ground in the team's colour with a few pyramids around it, in the middle of one of the sides of the map.
If you are carrying a flag (either your own team's or one one of the other team's) and you are shot then the flag is just dropped at that point (and obviously you die...) it's not returned to a base or anything. When your flag is brought back to an enemy base all the players in your team die (no point reduction though, so its not like you were shot) and start off in your base, with your flag in the base. Normally when you die you will respawn somewhere around the center of the map, nicely in the center of the fray!
The other main differences between CTF and free for all is that, as standard, in CTF there is no jumping and no power up flags, but there is still pleny of ricochet.
I personally prefer CTF to normal play. CTF places more emphasis on team play and tactics, there is less trigger happyness and a more controlled, thoughtful style of play. All league games are played in CTF.