Each series requires to have earned a certain amount of stars in previous series to unlock it and a total of 150 stars are required to unlock the final series. (rectifygaming.com)
Anyway, the small amount of maps on offer, along with the stripped back amount of game modes, does mean the multiplayer components feel a little thin compared to previous series entries. (wolfsgamingblog.com)
If the packaging for previous series is any indication though, we can make some assumptions of the special characters found in the fourth series. (animalcrossingworld.com)