Angryverse/Mii

Miis are customizable characters that debuted alongside the Wii via the Mii Channel, the Nintendo 3DS and the Wii U via the Mii Maker, the Settings menu via the Nintendo Switch, and on iOS, Android, and PC through the Mii Studio web app (considering that person has a Nintendo Account.) Their name is obviously a reference to the name of the Wii and the fact that the character can reflect the player (and of course others as well). They've since become a phenomenon and arguably the mascot of the Wii console.

Once the player has created a Mii, they're then allowed to place the character in a game of their choice and turn them into a playable character.

On the Nintendo DS, Miis are used in games like Personal Trainer: Walking and Tomodachi Collection. However, the DS itself does not have a Mii Maker app, meaning Miis saved to one game cannot be used in the other.

On the Wii, the Miis live in a small pocket-dimension called Mii Plaza. A new version of the Mii Plaza is present on the Nintendo 3DS in the application titled StreetPass Mii Plaza, where they are the main characters of Puzzle Swap and Flower Town, and the main protagonists of Find Mii, Mii Force, and Monster Manor.

Miis were previously available on smartphones with the Miitomo game, but that has been discontinued.

Wii
The Mii Channel is the app that allows Mii creation on the Wii menu. It can store up to 100+ Miis similarly to the Nintendo 3DS and Nintendo Switch and Wii Remotes are also able to store and transfer up to ten Miis to other consoles. It is also possible to see other Miis from TV shows and games.

Miis are intended to be an extension of the player, and in keeping with this spirit, the user can use them in several Nintendo titles for the Wii. Wii Sports is perhaps the best-known example of this, and it adds a further personal touch to Miis by saving game statistics and records for individual Miis. Miis will make cameo appearances as computer-controlled opponents, teammates, or within the audience. Miis have been used to serve as game file icons (profiles) within several games. Often appearing as just a head for identification, this Mii has no impact on the actual gameplay other than to identify a player in another way besides the name, or representation based on looks.

Miis are primarily used in games such as Wii Sports, Wii Play, Wii Fit, Wii Party, Wii Fit Plus, Wii Music and Wii Sports Resort. Players can also use their Miis, however, in other first-party games, most noticeably within WarioWare: Smooth Moves, Mario & Sonic at the Olympic Games, Mario Party 8, Mario Kart Wii, Mario Super Sluggers, Animal Crossing: City Folk (using their Mii's head as a mask) and in Go Vacation. The Japan-only Sega game Pachinko: Sammy's Collection is the first third-party game to incorporate Miis, while the Wii version of FIFA Soccer 08 is the first third-party game released in North America, Europe and Australia to use the Mii Channel. Many other games, like We Ski, and Guitar Hero World Tour and Sonic Colors also use Miis.

While a Mii's head always remains the same, its body varies between games. For example, in Wii Sports, the Mii's body is stylized, with spherical floating hands and bearing no arms, and Mii audiences or CPUs floating with spherical bottoms with no legs instead, but in Wii Fit its body is designed to look more natural, and its weight will be determined by the weight Wii Fit found of the player in Wii Fit tests. Sometimes Miis will wear outfits in context with the game. In Super Mario Galaxy and its sequel, the Miis can be optionally used for the planet's icon that represents the save file, the other option being to use Mario characters for the planets. Only the Mii's head is shown and it's shown in a sphere shaped like the planet. In Mario Kart Wii, Mii racers can be dressed in jumpsuits, or Mario style overalls for males and a Peach style dress for females, in Dr. Mario Online Rx, Miis appear in medical clothing, and in Metroid Prime 3: Corruption, where they appear as bobblehead dolls, they will be dressed up in bounty hunter Samus Aran's Power Suit. In MLB Power Pros, Miis are designed to look like regular Power Pro-Kun avatar, with legs detached from the main body. In Dance Dance Revolution Hottest Party 2, the Mii's body is formed more like a regular human. This design was, however, criticized by IGN's Lucas M. Thomas, who sarcastically commented that "[it] doesn't look disturbing at all."

While Miis are not playable in Super Smash Bros. Brawl, the creator of the series, Masahiro Sakurai, explained that Miis were originally considered to be playable in the game, but the idea was decided against due to fears of bullying. They would eventually debut in Super Smash Bros. for Nintendo 3DS and Wii U. They were used as avatars though.

Miis were incorporated in the downloadable Everybody Votes Channel, where Miis represented the voter. Up to six different Miis could be registered within the channel to use in voting. The channel was discontinued along with the Check Mii Out Channel by Nintendo on June 28, 2013, as they moved on to other next-generation projects.

Another Mii-centric channel, the Check Mii Out Channel, also known as the Mii Contest Channel (Miiコンテストチャンネル, Mī Kontesuto Channeru) in Japan, Europe, and Oceania, was released on November 11, 2007. Perhaps an evolution of an idea shared by Shigeru Miyamoto at the Game Developers Conference in 2007, this channel allowed players to upload their Mii characters and share them with other users. There were also popularity contests, in which players would design a Mii that would personify a specific idea or character and then vote on the Mii that would best fit the suggestion. The channel was available for free download on the Wii Shop Channel from November 12, 2007, until June 27, 2013, when Nintendo discontinued the channel along with the Everybody Votes Channel.

Nintendo DS
Although the platform lacks native support for Mii creation, a few games on the Nintendo DS console do support Mii functionality, and will work in conjunction with the Wii's Mii Channel.

Miis can be transferred from a user's Wii to supported Nintendo DS games via the Mii Channel. A code must be entered by the user to unlock the feature on the Mii Channel.

The Nintendo DS game Personal Trainer: Walking uses Miis to allow players to track their progress in the game. Players are also able to create Miis in-game. The Nintendo DS version of Final Fantasy Crystal Chronicles: Echoes of Time also uses Miis.

The life-simulation game Tomodachi Collection, only released in Japan for the Nintendo DS, also uses Miis and has a built-in Mii editor. Miis from the user's Wii's Mii Channel can be transferred to the game, and vice versa. Finally, a Mii game for the Nintendo DS! Even though it never released outside Japan.

Nintendo 3DS
The Mii Maker (Miiスタジオ, Mī Sutajio, lit. "Mii Studio") is the app that allows Mii creation on the Nintendo 3DS. It can store up to 100 Mii characters, much like the Wii and later Nintendo Switch, and includes more facial features than the latter console. The Mii Maker installed on the Nintendo 3DS can use facial recognition to generate a Mii, which selects facial features based on a photograph of a person's face taken with the system's cameras.

Unlike the Nintendo DS, which features limited support of Mii characters, its successor the Nintendo 3DS features Miis as a standard. Similar to the Wii's Mii Channel, the Nintendo 3DS features its own Mii-creating application called Mii Maker, which is more advanced than the Mii Channel.

Mii characters can be created manually with Mii Maker as on the Wii's Mii Channel, but they can also be created automatically through the use of the Nintendo 3DS's cameras. The system captures an image of a subject's face, and the application converts the image into a Mii likeness using integrated recognition software. Automated Mii character designs can be manually adjusted. Mii characters can also be imported from the Wii to the 3DS or from the 3DS to the Wii U. However, Miis cannot be sent from the 3DS to the Wii, as Mii Maker features an expanded selection of design parts that are not available on Mii Channel.

The Nintendo 3DS can generate and read QR codes that represent Mii characters. QR codes and pictures of Mii characters can also be transferred to an SD card in any picture format, and be used in various ways, such as posting them on a web page. Miis on the Nintendo 3DS can also be used in conjunction with the device's Augmented Reality software - the software includes a mini-app named 'Mii Pics' which allows the user to take a photo of their Mii within a regular photo, using an augmented reality card included with the system.

The first Nintendo 3DS game to include support for Mii characters is Pilotwings Resort. Miis obtained through StreetPass appear as non-player characters in Nintendogs + Cats. Mii characters also appear in Pokémon Rumble Blast, Mario Kart 7, and in many more games.

Currently, the most notable game to feature Miis in their entirety is Tomodachi Life, the sequel to Tomodachi Collection, which was only released in Japan for the Nintendo DS. This is also the first game to give Miis complete lines of dialogue as well as the first game to allow players to choose what Miis say. Miitopia is another Mii-centric game title for the Nintendo 3DS, also released on the Nintendo Switch in May 2021.

A feature on the Nintendo 3DS, the StreetPass Mii Plaza (すれちがいMii広場, Surechigai Mī Hiroba) makes use of the handheld's StreetPass feature, which data can be transferred between nearby Nintendo 3DS consoles in standby mode. As Miis are gathered in the plaza, they can be used in numerous minigames, with the initial two being Puzzle Swap and Find Mii (known as StreetPass Quest in PAL regions). In Puzzle Swap, players can exchange pieces of several jigsaw puzzle panels based on Nintendo games, in which there were initially seven, but this number increased with occasional updates. Find Mii is an RPG minigame in which players use the Miis they gathered to fight through dungeons, earning accessories for their Mii. Each Mii possesses a different type of magic depending on their color, and become more powerful if the player meets them more than once. These games can be optionally played with Play Coins, though the results are more random than with Streetpass Miis. On December 6, 2011, the feature was updated to include SpotPass functionality, as well as new puzzle panels, a sequel to Find Mii, a map showing where players met other Miis, Accomplishments and a music player.

Special Miis released by Nintendo and obtained through SpotPass can also be used in StreetPass Mii Plaza. They have access to all Puzzle Swap pieces and provide a level 5 player for Find Mii.

Wii U
The Mii Maker (Miiスタジオ, Mī Sutajio, lit. "Mii Studio") is the app that allows Mii creation on the Wii U. It can store up to 3,000 Miis (that's a lot!) and includes the same facial features used on the Nintendo 3DS. The Mii Maker installed on the Wii U can use facial recognition to generate a Mii, which selects the features based on a photo of a face taken with the Wii U GamePad camera.

Mii characters evolve further for the Wii's successor, Wii U. In addition to previous uses on the Wii, Mii characters are wholly integrated into the Wii U's social online network Miiverse, the WaraWara Plaza community where clusters of Mii characters crowd around the hottest games, and being depicted as personal avatars for individual Wii U players, who have the ability for twelve separate Nintendo Network ID User accounts that can be used on a single console at a time. User accounts with Mii representatives are used for both games and apps such as Nintendo TVii. Mii characters can be transferred from the Wii and/or the Nintendo 3DS to the Wii U, in which in the latter's case transfers between consoles can occur as many times as possible. Mii characters also return as in-game characters for certain Wii U games, which in addition to Nintendo-published launch titles such as Super Smash Bros. for Wii U, Mario Kart 8, New Super Mario Bros. U and Nintendo Land, they are also included in third-party titles such as Sonic & All-Stars Racing Transformed. In Mario Kart 8, there are 19+ amiibo suits when you tap an amiibo on the left side of the Wii U Gamepad based on the customizable characters.

The Legend of Zelda: Breath of the Wild uses an evolved form of Mii, UMii, to render non-essential NPCs.

Nintendo Switch
Miis can be used on the Nintendo Switch to represent accounts; unlike previous Nintendo consoles, users may optionally use a Nintendo character such as Mario as their avatar instead, but Miis can still be integrated into games as a playable character such as Mario Kart 8 Deluxe, Go Vacation, Nintendo Switch Sports, Super Smash Bros. Ultimate and New Super Mario Bros. U Deluxe. The Mii Maker is located within the console's system settings menu and, unlike previous Mii Makers, provides unnatural hair and eye colors. Miis can be transferred between Nintendo Switch consoles and imported from a Nintendo 3DS or Wii U using an amiibo figure. Miis can also be imported from a Nintendo Account. In Mario Kart 8 Deluxe, there are 20 amiibos registered after when you tap an amiibo on the NFC reader here on the Joy-Con (R), or on the top of the Nintendo Switch Pro Controller. Like with the Wii and Nintendo 3DS, the Nintendo Switch can hold up to 100+ Miis unlike the Wii U (which is less powerful than the Nintendo Switch) which could store 3000+ Miis. Why did you do that Nintendo?!

The first and the only Mii-centered game released on the Nintendo Switch possibly forever so far is Miitopia, a remaster of the 2017 role-playing video game originally on the Nintendo 3DS.

The Miis are also featured in Nintendo Switch Sports. However, the Animal Crossing Villagers new avatars called "Sportsmates" are also playable.

Other platforms
When the freemium mobile app (since shut down) Miitomo launched on iOS and Android devices, it was possible for the first time to officially create Mii characters without the need for a Nintendo console. Mii characters created on the app initially resembled their Wii U counterparts, with a later update introducing Nintendo Switch standards, and use the same attributes. Nintendo Account holders can opt to use the app to create Mii avatars without the need to link their accounts to any Nintendo console, with the option also available. Miitomo was also be used to support Mii avatars on other Nintendo apps for smart devices. For example, an update released for Super Mario Run on April 25, 2017, introduced player Mii icon customization options with the support of Miitomo, and its in-game costumes, via the same Nintendo Account. Miitomo was only available in 60 of the 165 countries/territories recognized by Nintendo Accounts by May 9, 2018, when it was discontinued.

On May 24, 2018, Nintendo introduced a browser-based Mii editor called Mii Studio. The editor is integrated into all Nintendo Accounts for users in all regions, including regions that did not originally have official support for Miitomo. Mii Studio supports all Mii attributes and standards introduced for the Nintendo Switch. Up to six Mii avatars can be created at a time, including any Mii imported from a linked Nintendo Network ID (also known as NNID).

In a pre-queue area for Mario Kart: Koopa's Challenge at the Super Nintendo World amusement area in Universal Studios Japan, Mii characters appear on several screens to showcase ride mechanics and safety precautions.

Angry Birds Miis
Many Angry Birds Miis exist. You can find them at miicharacters.com. You can use them in games such as Wii Sports, Wii Fit, Tomodachi Life, Miitopia, Mario Kart, Super Smash Bros., and many more games.