From Xsyon in the Official Announcements
The main discussion seems to be regarding safe zones. Some players are imagining 'safe switches' that can be turned on and off. That's not part of any plan. I am considering allowing tribes that want to war sooner than others to remove their safe zone if they so desire. A separate zone (as the mist clears) or server with no safe zones at all is also under consideration depending on the world's population. My goal is not to impose new limits as solutions but to give more choices.
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you won't be able to turn your tribe city into a safe spot that doesn't allow other people to attack your tribe after prelude. (no switches)
There will be plenty for you to use in order to better defend against attackers, and it's up to tribes to determine how well they want to setup defenses inside their cities.