Team Fortress Classic is a first-person shooter game developed by Valve and published by Sierra Studios. It was originally released in April 1999 for Windows, and is based on Team Fortress, a mod for the 1996 game Quake. The game pits two teams against each other in online multiplayer matches; each member plays as one of nine classes, each with different skills. The scenarios include capture the flag, territorial control, and escorting a "VIP" player.