[kalniel]

Well I think DoW covers all the other games in the series too, as they're so cheap to buy as a bundle (ditto SupCom and Forged Alliance). You do need a disc each of DoW if you're playing the same game, otherwise yes one of you could buy DoW, one Soulstorm and one Dark Crusade if it was three of you, but then each of you would be limited to playing different races in multiplayer.