
Originally Posted by
Morrison
for all the older games, they're likely using emulators and i'm pretty sure they use parsec, which is a program that allows one computer to run the game and be accessed remotely from other computers. so they're not going through the game's online services, they're just setting up games/matches as if it were couch co-op/multiplayer, and the other participants are joining the session remotely from their own homes as player 2/3/etc.