Guest B

Wii Games
Guest B is 1 of the 6 Guest Miis. These Guest Miis are pre-built miis that you can use in games where you can play as your own mii. The Guest Miis were created in case of someone not having a mii in a game where you play as a mii. They are in games like Tomodachi Life, Miitopia, Wii Music, and of course, the Wii Sports games.

Wii Sports TAS
If you search up Wii Sports TAS on youtube, the top result should be by a person named DyllonStej Gaming. In his videos, Guest B is the mii that is used. In the "Beat the Champion" speedrun TAS video, Guest B defeats Matt without getting hurt. In the video, nobody touched Guest B besides Matt. Matt was the only Mii that connected a punched. Guest B blocked the punch, resulting in Guest B going the entirety of Boxing in Wii Sports without getting hurt and not without getting hit. DyllonStej also made Wii Sports Resort TAS videos. Once again, he did a "Beat the Champion" speedrun TAS video for Swordplay Duel. His Attack Pattern in the Swordplay TAS videos is spinning the sword around him in a circle quickly.