I'm guessing you are talking about CK2. There are two versions: Gamersgate (only available from them) and Steam (from anyone else, such as Steam themselves, Amazon, and the boxed edition).
GG is a game download service not unlike Steam except it has no client, does not update automatically, has no DRM (or DRM-like features, as some people accuse Steam of having). You cannot install while offline. And yes, you can play disconnected from the internet, you can copy it around by USB key or whatever, it still works fine, DLC is available from GG via the in-game store - that of course requires internet connection to buy.
The Steam version will of course install their client and so on, requires you to be online for the installation process, but it does allow play while off-line - indeed you don't even have to have the Steam client running, you can just execute ck2.exe directly and that works fine. You can copy the game around just as with the GG version - the executable is not Steam-ified in any way (unlike, say, EU3 before 5.1).. DLC is available from Steam and too requires a connection to buy and install.
With both versions it is intended that DLC work while offline, although there have been some reports of that not working properly in the current patch.
GG is a game download service not unlike Steam except it has no client, does not update automatically, has no DRM (or DRM-like features, as some people accuse Steam of having). You cannot install while offline. And yes, you can play disconnected from the internet, you can copy it around by USB key or whatever, it still works fine, DLC is available from GG via the in-game store - that of course requires internet connection to buy.
The Steam version will of course install their client and so on, requires you to be online for the installation process, but it does allow play while off-line - indeed you don't even have to have the Steam client running, you can just execute ck2.exe directly and that works fine. You can copy the game around just as with the GG version - the executable is not Steam-ified in any way (unlike, say, EU3 before 5.1).. DLC is available from Steam and too requires a connection to buy and install.
With both versions it is intended that DLC work while offline, although there have been some reports of that not working properly in the current patch.
