Team Fortress Arcade
Team Fortress Arcade is an game created by Eric Ruth, who had previously made side-scrolling versions of Halo and Left 4 Dead. It is a side-scrolling game in which the player, or players, take control of any of the 9 BLU classes from Team Fortress 2 and progress through 9 levels, each of which has one of the RED classes as a level boss – as well as a secret tenth boss which ties into the Portal franchise. The game supports up to 4 players at any one time.
The game was released on the 29th of September 2011, and is available to download for free from the external links section, and also includes an interview with the developer of the game.
According to the developer in the interview, he states that he "intends on updating the game in a couple months with some new modes, difficulty challenges, a player VS player match-up and yes, online co-op." When guest hosting on KritzKast, he announced that he had been acquired by a gaming company and thus would not be able to continue support for the game for copyright concerns.