Ability to pick which clan to war with.

Ability to like invite another clan to a clan war. If both clans accept then the clan war will be started. Great to have fun with friends :D.

And then you choose a weak clan so that your clan wins easily ?

At first, I thought it would be nice but then I thought.....

"What if someone creates a second account, gets 10 people to join, and then join a mutual war being a crappy clan to help out another?"