Pokémon Rumble World

Pokémon Rumble World is the fourth game in the Pokémon Rumble series, and the first one to feature Miis as player characters. It is a free-to-start game, although it also received a physical release with all microtransactions paid for already. Miis are used for all non-Pokémon characters in the game, including the player. The ability to choose the Miis of non-player characters from other players' Miis can be optionally unlocked.

Story
The game starts with the king of the land telling the player's Mii about a magician who had 10 different Pokémon species, and asks the player's Mii to use his only Pokémon, a Pikachu, to gather more. The player's Mii then catches Pokémon in the King's Training Field and shows them to the King. After this, the player's Mii heads to the castle's courtyard to buy a hot air balloon and set off to gather more Pokémon from surrounding regions. After the player's Mii gathers 10 new species of Pokémon, the magician sends the King a letter challenging him to a battle, which the player's Mii wins for the King. The player's Mii then continues gathering Pokémon and battling the magician, along with meeting other characters such as the Prince.

Mii settings
Within a player's profile settings are settings for the player's Mii.
 * Messages are various short bits of text displayed under various circumstances:
 * Greetings are displayed in the castle courtyard.
 * Help Requests are displayed when the Mii is attacked by Pokémon in a stage.
 * When Defeated messages are displayed when the Mii is KOed by a Pokémon.
 * When Helped messages are displayed when a Mii is rescued in a stage.
 * Change Clothes lets the Mii change clothes from various outfits the player can buy. Some clothes reflect the Mii's favorite color.
 * Partner Pokémon lets the player choose a Pokémon that is displayed alongside them when they are called as an adventurer. This must be unlocked from the shop.
 * Expressions, Backgrounds, and Frames lets the player choose how their Mii's fullscreen profile looks.
 * Change Mii lets the player change which Mii represents them.

Adventurers
Other players' Miis can be called to the game. Miis can be called for free using StreetPass and SpotPass, or they can be called via the internet once per day for free and for a cost of Play Coins afterwards. These adventurers can appear in stages or in the castle courtyard alongside their partner Pokémon. They can send the player to a specific unlocked level for in-game currency. Various game stats about the player whose Mii it is can also be displayed. These adventurers can show up as the store manager, and they can be manually assigned to other NPCs with an optional shop item.

Miis in stages
Miis can be found in stages, and some story challenges involve protecting a Mii as the main objective. Miis called as adventurers can be found in stages under attack by wild Pokémon, with the player's current Pokémon having to defeat the wild Pokémon to help the Mii. Regardless of if the Mii is found in a stage or there to be protected, they will periodically give the current Pokémon items such as Potions and X Attacks. If a Mii is rescued while another Mii is with the Pokémon, the second Mii will disappear upon being rescued. A rescued Mii will walk onto the hot air balloon with the Pokémon at the end instead of the player's Mii already being on it.