The main Idea is that you are able to select the Era of Play alongside with the map. For example , you have chosen muld as the map. Then you have the choice to Play in a Medieval Muld (even though that would mean that you were an indian and I don;t think their population in that area could provide a fine zombie horde so lets keep the Medieval Era for Maps in Europe) an Industrials era Muld ( like the one in the game now) , a Modern era Muld (What I think that is already for the game in the game ) , A futuristic Muld (...) Each era will have different items and also some items will be easier to find. For example in the Medieval era it can be easier to find a Saw or an Axe while in modern era you will find mostly Phones , iPads and Food also some buildings like hospitals will have their own power generators . Each era will have different Professions. Medieval : Blacksmith , Baker, Builder, Slave, Soldier, War Machine Constructor, Philosopher, Shaman , Scientist, Cleric, Fisherman, Farmer , Hunter etc Industrial: Policeman, Investigator, Military , Builder etc Modern : Many of the professions we have today Futuristic : Space Explorer + Same professions as in Modern but there are more traits like Genetically Reconstructed etc. I know that such feature in the game requires very much work but if the community really likes it I think it can be added officialy in the game (after its release) as a DLC . I also know that I will get a Comment saying that something like that can be done by a mod or that it is already completed but I just think it is a feature that will be fun to be added in the Original Game.