There are new backgrounds during battles, to be exact one for each existing clan. Well, I'm not really sure about this. Do the leaders have their own?
While playing I realized this one (http://kirlad.net/shared/ur/unknown.jpg) which should be the leaders place. Do you think it is? or could be another (future) new clan? In my opinion it doesn't fit very well with leaders, as they don't fight well together should they have a "base"? And is too soon to include a new clan, but many things could make this background to be included.
In my observation, the clan with the most cards (for ex. your opponent has 4 Sentinel cards and you also have 4 Sentinel cards in hand) the background will show the police station or the sentinels back ground.
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