I know two people actively playing: one the thirteen year old son of a friend who loves to build his own little settlement, complete with home made trees and his own pen for keeping livestock; the other is my 13 year old nephew who enjoys griefing servers by going in, hacking away at someone's beautifully wrought construction and replacing it with a brick cube. Oh, and suiciding until kicked. Yeah, the little hellion has problems.
I'd get into it, but it looks way too addicting and I think I'd spend more time building in that virtual world than in real life.
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