The Summer Weekend War is a tournament-like-thing with war. One clan vs. another clan of about equal strength will duel it out in an average war. As far as I can tell, it will all fall down to prestige (prestige will be reset to 1,000 before the war) in such a way that even the clan ranked, I don't know, 20,000 on the powerful side has a chance to outlast the, again not knowing, 1 ranked most powerful, the top 200 will have the chance to do the test (clan page, check it, even if your clan is not in the top 200) and it'll show you. That's all I got, scoop wise.