#15
Eco is the strangest recommendation on this page, in the best way. You are not just building and surviving. You are collectively trying to stop a meteor from hitting your planet while managing the ecosystem you are disturbing in the process. Governance systems, shared economies, property law. I have never played a sandbox that generates political arguments as reliably as this one. Private-server setup is well-suited to a committed group. The reason it is an honorable mention rather than a ranked entry is that it needs investment to pay off. A group that goes in unprepared will spend the first hour confused. A prepared group will be talking about their session for weeks.