For the heck of it I went ahead and started a game. One city challenge, pangaea, six other civs, settler level. Picked Peter (philosophical, expansive, research institute) and world buildered all the wonder resources I lacked into the nearby terrain as well as I slight passage to the ocean. Fun times!
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Every building and wonder in the game. Also seven holy city. (though only one shrine, the rest of the prophets were merged) Got legendary nine times over, almost 500,000 on a normal speed game. Even though my military consisted of a single axeman and scout (upgraded through the ages) and later a nuke, my power level stayed #1 or #2 consistantly.