絕地要塞
The plot of "Team Fortress 2" is progressed outside of the game itself, usually in the form of short videos or comics. In April 2014, Valve introduced the "Team Fortress Classic" mercenaries, excluding their respective Medic, into the plot of "Team Fortress 2". A catch-up comic released on the TF2 website released for free comic book day revealed that Team Fortress Classic is set in alternate 1930, and that the game takes place during the Gravel Wars era of the timeline, along with the fact that the classic engineer is the father of the engineer in "Team Fortress 2".