I found Anarchy Unbound and it is straight up survival anarchy with zero safety nets. There are no rules at all and it says no bans. It also says there are no resets so the world keeps its history.

People can grief anything and duping is allowed too. Players make alliances then backstab each other and that is just part of it.

The only thing they block is flight. Movement is supposed to matter so running away takes skill and travel stays dangerous. Everything else is fair game and whatever you build or destroy is going to stay.