@papaya @Goshan
use extra citizen like this…example if your citizen is 18…max first the 18 example…use for 2 market, four citizen each so thats 8. then 2 mill thats another 8 citizen now 16 has been used use the last 2 citizenfor sam battery…now its 18/18…now you can upgrade one more so use it for tank depot for 6 citizen…now the next will give you error…and dont use extra citizen in university you will be banned. well i use my extra citizen for resources not for buildings. expecially if there is event.