Mii Central

Mii Central (Japanese: みんなのMii Minna no Mii; Everyone's Mii) is a feature exclusive to the Nintendo 3DS version of Miitopia. It combines the Mii popularity system from the Check Mii Out Channel for the Nintendo Wii and Autoassign, a feature introduced in Miitopia that allows automatic Mii Cast role assignment. Using this feature requires SpotPass to be enabled and an active internet connection.

Description
Mii Central is an online service for the Nintendo 3DS version of Miitopia that allows the player to play the game without having to create additional Mii characters. A player may upload a Mii to the Mii Central by going into the Party menu, selecting a party member Mii, and then going to the Details menu and clicking Post. Once the Mii is uploaded, the Mii may be subjected to a voting system determined from the questionnaire or casting data. This will determine the Mii's visibility when being searched by other players or likeliness to be cast in particular roles when Autoassign is used. However, the player can not upload a Mii to the Mii Central if the Mii is one of the following:
 * A Mii downloaded from Mii Central.
 * A Special Mii, distinguished by his/her base design wearing golden pants.
 * An edited Mii received from another player.

During Mii creation or Mii Cast role assignment, the player may choose to pick a Mii from Mii Central. By default, the list shows a random assortment of Mii characters. However, the list changes over time based on the tallied questionnaire votes on the uploaded Mii characters. The higher the Mii's popularity, the more likely he/she shows up on the Mii Central list. Specific to the Mii Cast, another online method of picking a Mii is by using the Autoassign button. Clicking on it once will change the selected role's Mii into a random Mii from Mii Central. Questionnaire votes and casting data from other players influence which Mii characters are more likely to be picked by Autoassign for a given role. If the casting group contains multiple Mii characters (for example, Greenhorne), the player may change all at once or individually. The former option will apply Autoassign on all Mii characters in the casting group, while the latter option will allow the player to pick one of the roles the player wants to use Autoassign on.

If the player needs a specific character, the player can search by name on Mii Central. It will then return all Mii characters with the inputted name as the search result, if any. In the Japanese version, the list accepts both hiragana and katakana variations of the inputted name.

In the Nintendo 3DS version of Miitopia, certain roles are automatically assigned by the game as long as the player already has SpotPass enabled and the Nintendo 3DS system connected to the internet. Casting groups that have this apply include Greenhorne, Castle Guard, Neksdor Town, Elven Retreat, and Travelers' Hub. Certain individual roles, which are the Roving Photographer, the Quizmaster, the Prodigious Postman, the Roaming Gourmet, the Nintendo Fan, and the Scholarly Pioneer, can also be automatically assigned by the game via SpotPass. The way the game decides the Mii characters for the roles is similar to the Autoassign feature.

Even though the Nintendo Switch version of Miitopia does not have SpotPass and thus most Mii Central features, the player is able to access the Mii Central list of Mii characters based on questionnaire votes by choosing "Popular" as the external Mii source. There is also a setting in the "Mii characters" menu to allow the Travelers' Hub to generate visitors using Mii characters taken from "Popular". The player is not only required to have an active internet connection to use these features in the Nintendo Switch version of Miitopia, but also an active Nintendo Switch Online subscription.

In Miitopia: Casting Call
Mii Central integration was not available initially in the Japanese version of Miitopia: Casting Call. This feature was added to the app's casting system via an update on November 30, 2016.