[citation][nom]bgaimur[/nom]and prepare to be disappointed. News flash: Blizzard cannot enable "offline play" without handing you their server code. An "offline client" in client-server architecture is simply a married client/server. This means that Joe Hacker now has everything he needs to build, test, and effectively deploy an online-compatible hack of the caliber of d2hackit/duping methods/packet sniffers/etc. The moral of the story here is this: if you do not have proper security measures in place so that the integrity of your account and everything that is encapsulated inside your Blizzard account cannot be compromised, be prepared to wait on hold for Blizzard support for a few hours with everyone else who thought their $4 (is it even 4 dollars?) was better spent elsewhere. Let's not forget to mention that the mobile app is even cheaper (free?)[/citation]
bgaimur, that is yet to be seen, all of the game data is local on the system for single player and most of it is local for online multi player with the exceptions of data on NPC/Monster Stats & Spawn points/frequencies.
As for the Server/Client married that's only true in online only games with a game that supports a single player campaign there is always the ability to offline it it just depends on how much work someone is willing to do, which so far from what I'm seeing is the following
Build an offline character save subsystem which removes the requirement for connections to the server to load character data
Remove or disable the API for the auction house for "Lite" installs
If all Spawns of monsters/NPCs are controlled by a server side triggered macro that's able to be ported easily enough
Patch the DRM to require a callback to the server at certain intervals instead of always on with the system making the call via packets protected by a 2048bit RSA key
The downfall is there will always be people who had the "Lite" client installed that now want to go to full with the AH enabled & any other online enabled features that would require Blizzard to have a way to upload the character data to the server for verification before it can be used in the live/online environment, or just tell the player they can't import the data and have to start from scratch.