StreetPass Mii Plaza

StreetPass Mii Plaza is a pre-installed application on the Nintendo 3DS developed by Nintendo that relies heavily on StreetPass connectivity to play its games. It allows players to create a profile using any Mii that they have made in the Mii Maker, which will be sent to other users via StreetPass when connected, and used to play games. Two games which utilize the player's Mii (three after the December 2011 update) can be played in the Plaza: Puzzle Swap, and Find Mii (called StreetPass Quest outside of North America). The game's only unlockables are Nintendo-themed accessories which can be used to dress up the player's Mii, and three dimensional scenes featuring recent Nintendo games or events.

Features
StreetPass Mii Plaza allows the creation of a profile that players can customize with their personal information, which is sent to other users upon connecting via StreetPass. This information includes a Mii, which is used as a player character while in the Plaza, a greeting, a birthday, the 3DS' registered location and minor details such as a favorite hobby or dream. Players can choose to make some of this information private if they wish, and can change the information in the Settings sub-menu at any time. As long as the player has the wireless communications switch turned on, StreetPass enabled, and the system closed, the data is transferred between any wireless-enabled 3DS system within range. A notification light on the 3DS turns green to indicate when another 3DS has been detected, even when the software is closed.

StreetPass Plaza is the location where the player's Mii resides. The Plaza is lush with green lawn and small plants, and features a yellow arch adorned with a grass root as its front entrance. Initially it begins empty and the music begins quiet, but as additional Miis are invited into the plaza via StreetPass and online games such as Mario Kart 7 or Mario Tennis Open, the plaza grows, and the music becomes more dynamic. Upon opening the software after a connection has been made, the front gate of the Plaza is shown with the player's Mii greeting any new Miis that have been encountered while the system was closed, before inviting each to take residence in the plaza and play Find Mii and Puzzle Swap with them.

The player is given the option of playing two games (three games after the December 2011 update) to unlock accessories and 3D images related to various Nintendo series, by using either Miis obtained by StreetPass or Play Coins. After the December 2011 update, additional features were introduced, including a slideshow for completed Puzzle Swap panels, a world map which shows locations that differ to the player's, an achievements list, and a music player for listening to the application's various tracks.

Puzzle Swap
Puzzle Swap features various different puzzles that the player can complete. Players are given one piece to start off with, and more can be obtained by StreetPassing with other people. After StreetPassing with someone, the player is then entitled to take a puzzle piece from them (and vice versa) and add it to their collection. If another player does not have any new pieces, nothing is gained. Players can also spend two Play Coins to buy a random puzzle piece to any incomplete puzzle they have. However, the puzzle piece may be a copy of any earlier acquired pieces, and will be of no use. Once a puzzle is completed, a three-dimensional image of the puzzle can then be viewed.

While the initial puzzles consisted of fifteen pieces, the December 2011 update included several puzzles with either twenty-four or forty pieces, as well as the ability to receive new puzzles through SpotPass. Additionally, the four center-most pieces in the twenty-four piece puzzles and the eight center most pieces in the forty piece puzzles are pink. These pink pieces cannot be purchased with Play Coins, and can only be obtained by StreetPassing other people who have obtained them.

Mario-themed Puzzle Swap Panels

 * Mario and Bowser (15 pieces)
 * Super Mario Galaxy 2 (15 pieces)
 * New Super Mario Bros. Wii (15 pieces)
 * Super Mario 3D Land (40 pieces)
 * Mario Kart 7 (40 pieces)
 * Donkey Kong Country Returns (24 pieces)
 * Mario Tennis Open (40 pieces)
 * New Super Mario Bros. 2 (40 pieces)
 * Luigi's Mansion: Dark Moon (40 pieces)
 * New Super Luigi U (40 pieces)
 * Heroines (features Peach, Pauline, Rosalina and Zelda.) (40 Pieces)

Find Mii
In Find Mii, Miis are utilized to fight their way through several enemy-filled rooms to free the player's Mii from imprisonment. Mario-themed accessories such as character caps can be obtained and later be used to dress up the Miis. When another 3DS is detected, its profile Mii will join in on the game. Players can also hire a wandering hero for two Play Coins, with a limit of up to ten in a single party. However, these heroes are usually very weak (Level 1 or 2) and take the appearance of a dog or a cat depending on the players' preference for cats or dogs which can be adjusted in the Settings menu.

A sequel to Find Mii, known as Find Mii II (StreetPass Quest II outside of North America), was made available in the December 2011 system update. It is similar to the original, but features tougher challenges. It can only be played once the first Find Mii game has been cleared two times.

List of Mario-themed hats

 * Mario's Cap
 * Luigi's Cap
 * Toad Hat
 * Bowser Hat
 * Yoshi Hat
 * Yellow Yoshi Hat
 * Light Blue Yoshi Hat
 * Pink Yoshi Hat
 * Piranha Plant
 * Warp Pipe Hat
 * Boo Hat
 * Shy Guy's Mask
 * Donkey Kong Hat
 * Peach's Crown
 * Daisy's Crown
 * Chain Chomp Hat
 * Wario's Cap
 * Waluigi's Cap
 * ? Block Hat
 * Penguin Hat
 * Blooper Hat
 * NES Hat
 * Famicom Hat
 * Pixel Mario Hat
 * Super Mushroom Hat
 * 1-Up Mushroom Hat
 * Fire Flower Hat
 * Super Star Hat

Enemies
In Find Mii and Find Mii 2, the player has to fight through several ghosts in order to save their Mii. Here are a list of enemies encountered during the quest:
 * Ghost: The main ghost, easy to defeat.
 * Blue Ghost: The second main ghost, these ghosts have higher health. Fire magic will defeat them easily but water won't work, in the sequel, they can create mirages of themselves which can easily confuse a player.
 * Blood Ghost: A bigger version of a normal ghost with a more menacing look and higher health, Water works against them, but fire won't.
 * Armored Ghost: A suit of armor with eyes inside the helmet, these ghosts are like normal ghosts but low leveled warriors are not a good choice for these ghosts.
 * Armored Demon: A bigger blue version of Armored Ghosts, they are still unable to be defeated by low ranked warriors, but high leveled shouldn't have a hard time with them.
 * Armored Fiend: The final normal ghost of the game only encountered at the top of Mirage Tower, this ghost guards the player's Mii and must be defeated, like every other armored ghost, this ghost will be difficult to defeat with low ranked warriors.
 * Ultimate Ghost: The final boss of the game encountered after defeating the Armored Fiend, this purple ghost takes several hits to actually defeat, but teams of different ranked warriors will defeat the ghost. It is also the second boss of the last stage in Find Mii II. In the Sequel, it spews Level Down Gas.
 * Dark Lord: The final boss of the Find Mii II game encountered after defeating the Ultimate Ghost. It takes many hits to defeat. It also spews Level Down Gas.

Magic
In Find Mii and Find Mii 2, each hero has a different magic spell depending on it's color the player has picked on the Mii Maker. This is a list of all Magic performed by the heroes.
 * Red: Flames are put on the ghost. This comes helpful with Blue Ghosts.
 * Blue: Same as Red, but helpful with Blood Ghosts.
 * Brown: Summons a hero, who is always a bunny. This heroes level will be +1 of the hero who summoned it.
 * White: Brings light to the dark, the second last room in Find Mii makes use of this magic.
 * Yellow: Whirls up a sandstorm, this is needed for the room before rescuing the princess, where two heroes with this ability need to be teamed up to wear noxious poison off.
 * Green: Temporarily strenthens the next Mii up to 2 levels.
 * Light Green: Puts the enemies to sleep.