The guys behind Tree House Ninjas talked about the way they helped to build the environments in Wolfenstein II.
Tree House Ninjas is a young studio, which has a lot of seasoned environment artists. The main focus of the company is environments and back in the day they helped Machine Games with the production of some of the cool scenes for the game. The trouble was that they didn’t have the right to have the engine on sight, so they had to adapt quickly.
Basically, they had to figure out how to assemble the environments, make everything super modular and they assemble everything together back in Sweden. Check out the talk for more details.