So basically we noticed that mansions are really really rare.. then we thought about making the world border bigger, but zick had the idea of another world that does not have a border and can be used for future updates as well if Castrovalva world doesnt include the new stuff
Basically, this new world called Adventure, will be like normal survival world, all builders can access it with their tardises. Build, mine etc.
Keep in mind there are no borders except of course the 30 million block border that minecraft has by default, so this world is exactly made for adventuring. Live map also shows this world for all builders.
Don't know about you, but I'm off to find a mansion!
PS. This world is concidered permanent, I dont think it needs reseting ever.. But never say never.. anything can happen, so don't blame us if one day the world resets.
You can use schematica to "keep" your builds, more info about that on the forums.