Hmm, not sure if it's old news..
But I just went onto my alternate account's profile page, and saw something that says that I can have a free name change for once..Here is the screenshot..
He has the box to change his mafia name.. only one-time change!
I have searched on my account but I don't have it... I guess it is a new feature that only available for mafia who has not changed his mafia name yet..
