Frontlines: Fuel Of War is currently completely broken on Steam. While Steam still allows you to purchase the game for $49.95US, the download does not include critical files required to launch the game. Valve has had the game on the store for the past few days, and is yet to fix the problem. A quick look at the Steam forum for the game shows how widespread it is. A user at the forums has come up with a manual fix to download the missing files and copy them in, however this still will not fix the single player. It is recommend to avoid purchasing the game from Steam until this issue is resolved.