Clan owners are struggling to organize a clanwar between two clans in one community how are they going to do it between different communities? Lets say you do the war for tomorrow and by then everyone has signed up for the war. Some people maybe have plans for tomorrow, or something suddenly occurring in their planner. They won't be able to play, then the opposite team will fail attending the match. I know you are going to say, "we are going to have a lot of subs", but its a really though work and you can think about it deeply.
No support.