This is the same world seed as the one I downloaded before, but I built a bridge from the strange new spawn point, and have surveyed farther away too. I also have replaced most of my old boosters with gold power track, at least on two or three of the lines available. Return to main base from outposts by way of Portals, it's the only way, (except from the first base you get to from the spawn point, which you have a choice of minecart return or Portal).
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I have explored this world extensively, and it's a rich one. Mine tracks total many tens of kilometers long going in all four directions. Lots of diamonds, four large bases, one on each mine cart track. Many mob spawners with booty, huge caves that can be explored forever.
NOTE: For some reason my spawn point moved, so I added torches and signs to help you navigate your way to the main base. You will travel through two minor outposts (with beds and supplies) before reaching the main base, which you will recognize by the glass structure. This update is the same as the first one, but with added help getting to my stuff from the new spawn point.