Heroes of Might and Magic 3. The game itself being great for multi-player aside, I used to play online tournaments with US players, during US evening hours whil

Heroes of Might and Magic 3. The game itself being great for multi-player aside, I used to play online tournaments with US players, during US evening hours while in Russia. That made me skip a bunch of classes in college, and realize instead of going to classes and getting As I could skip most and get Bs anyway; that translated into getting a dev job early in college, and set me up very nicely in my career. Stars! was another really nice multiplayer game (PBeM), I met some people irl from playing that and hanging out on IRC channel. ADoM back in the early days, playing it and finding out game lore from some mix or forum rumors and looking at strings in the exe felt special, the community around the game was great. Not community-related, Fallout 2 I think might be the best CRPG game ever as far as RP goes, you could really get away with playing a peaceful character that barely ever fights, and you could also become a maniac hated by the whole world and still have meaningful gameplay. Settlers 2, for some reason that's the only game I can basically just keep playing forever even though I ~never played multiplayer or never did anything online with it.