will players be able to build assets for the world and then sell the assets to other players in exchange for nxt?
if there is something akin to property rights can property be bought and sold with nxt?
Yes but not natively in the game. There will be an in-game currency that is "backed" by an MS currency, mainly to provide transparency. There will be a 1-to-1 ratio of player accounts to Nxt accounts but that will be managed by our end. We will most likely have an "advanced user" option to allow players to transfer items out to their own Nxt account, but it will come with conditions since we will not be responsible for lost passwords, hacked accounts, etc,
what about property rights? can anyone modify anything? so like if i make this amazing castle can people come along and donk it up?
Not all items in the game will be in the blockchain / property register, but those that are will have a public "title", just like an automobile title, that says who owns the creation. Transfer the title and the ownership of the item transfers, which allows for a market place of virtual items where artists and builders basically have a decentralized DRM system for their creations. You will be able to tell the difference between an original virtual Picasso and a perfect digital copy, thanks to Nxt.
Creators can specify whether an item can be destroyed based on what interactions they allow, with entire planets at the lowest level. In our universe, creating your own planet is the equivalent of launching your own Minecraft server. You are owner of your planet and can choose what to allow. You can take your creations to another planet, but some planets might not let you take your own creations there, or might ask to whitelist your creation first.