BZFlag is a free 3D online multi-player multi-platform tank battle game. It was one of the most popular games ever on Silicon Graphics machines and continues to be developed and improved to this day.

BZFlag allows players to register their name, also known as their callsign. Some servers provide additional benefits for registered users, such as voting in polls. Another advantage is that players can not use another player's registered callsign. To register a callsign, visit the forums and register an account. The username and password on the forums will be used as callsign and password in the game.

The game has four main teams: Red, Green, Blue, and Purple. In the Free For All and Capture The Flag game modes, each team works together to fight the other teams. Teammates should not shoot each other in those modes. In the Open Free For All game mode, the teams do not matter, and it is allowed to shoot any tank for points.

There is also a Rogue class that can shoot any other tank, even other Rogues.

In the Rabbit Chase game mode, team selection does not matter. The server will automatically set the player's team to either Hunter or Rabbit.

Servers can choose to limit the number of players per team or disable a team entirely.

Game Modes:

There are four main game modes. Some servers may use custom plugins to create variations of these game modes.

Free For All (FFA)
In Free For All, also known as Freestyle, the objective is to shoot enemy tanks to earn points. The four main teams should not shoot other team members as this will result in a penalty. Rogue players are allowed to shoot any tank, even other Rogues.

Open (Teamless) Free For All (OpenFFA)
In OpenFFA, the objective is to shoot other tanks to earn points. Teams do not matter, and all tanks can shoot other tanks.

Capture The Flag (CTF)
In CTF, each of the four main teams can have one or more team flags and one or more team bases, both colored to match their team. For each team, the objective is to capture enemy team flags by grabbing them and bringing them back to their base. Each team also tries to prevent the enemy team from capturing their flag.

Rabbit Chase
In this mode, a single Rabbit is chosen by the server. All of the other players will be Hunters. The Rabbit can score the most points, but it is also the most vulnerable. When the Rabbit is killed, the server selects a new Rabbit.