I'm having a hard time thinking this setup out. My idea is this: There is a world where each screen is a place on a grid, and there is a variable that randomly picks a playfield for each of those screens in order to build the world.
At the moment, the best I can think up in terms of a setup is having a variable for each possible room on the grid, and a variable that picks out a playfield for that room, so when the player goes to that room on that grid the roompicker variable picks a