OSW is off system war. It's use to be more common than it is now. It's just a war between two families or clans. They farm and strip etc. until one of the clans backs down or until a mutual cf.
And you'd do it to defend your clan, to avenge and insult or most importantly for me, because they're fun.
unlike a system, war, OSW can last for a day or a year, or however long bit parties wish to carry on. There is no score board, and the terms for victory differ from war to war.
used to be more common than it is now? how come I'm always finding new wars to join then? i came back to KaW, within 1 n half weeks iIwas already back into OSW :L
OSW is actully getting it's popularity back lol there are some great ones going on now. It is what made this game popular and fun and is still the greatest part of this game.