Hello, I apologize for my lack of knowledge on the subject.
I would like to make a small server for some old friends where It basically is a small continent, within the continent there are areas you enter to get to custom Adventure maps, and in those maps you have custom skinned NPCs with random loot in chests. I don't even know if this is possible, or if this is the right thread to be honest. But I'd like to know how it all works, if you can get custom NPCs in a mod, will it transfer to a server. If I can make a server run, can you enter an area that teleports you to a custom made world which then has custom randomly generated loot chests, within the custom world? Think Diablo style. I've begun working on my small continent but If I make custom worlds I want them to be separate, so you can run through them over and over like a dungeon/instance in some random MMO.