絕地要塞
Following the success of "Team Fortress" as a "Quake" modification, Team Fortress Software began development of a sequel. Interested in the project's potential, Valve hired the team to develop "Team Fortress 2" on the modified "Quake" engine utilized by "Half-Life". The partnership was announced in 1998, developed in parallel to "Team Fortress Classic". However, the game was not shown publicly until a year later at E3 1999. Introduced as "Team Fortress 2: Brotherhood of Arms", the game showcased multiple unprecedented technologies for its time and won several awards including "Best Online Game" and "Best Action Game". In June 2000, Valve announced that "Team Fortress 2" had been delayed further, attributing this to their rebuilding of the game on a new, proprietary in-house engine that is today known as the Source engine.