Team Fortress Classic

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 puts 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.

Valve hired the developers of the Team Fortress mod to develop Team Fortress Classic using its GoldSrc engine (used in their 1998 game Half-Life) to promote the Half-Life software development kit. It received generally positive reviews, although the graphics were a point for criticism. In 2000, Valve released a standalone version, Team Fortress 1.5, with new character models, maps and other features. Team Fortress 2 was released in 2007.