BZFlag is a 3D, multiplayer, tank battle zone, capture the flag game that pits players against each other in a networked environment. It runs on Windows 95/98/NT/2000, Linux, MacOS

BZFlag (an abbreviation for Battle Zone capture the Flag) is a three dimensional first person tank shooting game. It was originally written by Chris Schoeneman for the SGI family of computers based off of the classic Battle Zone game. Current open source development is maintained by Tim Riker, and a team of project administrators.