Isabelle (しずえ, Shizue) is a major character from the Animal Crossing series. Since her debut in Animal Crossing: New Leaf as the player's secretary, Isabelle's popularity has resulted in her becoming a mascot of the Animal Crossing series, much like Tom Nook and K.K. Slider.
In Animal Crossing: New Leaf, Tortimer has retired from the position of mayor. Upon moving into the town, the player becomes the subsequent mayor, and Isabelle will begin assisting them as their secretary. Despite being slightly naive and occasionally scatterbrained, Isabelle is nevertheless eager and hardworking.
As the secretary, Isabelle aids the player in signing town ordinances into law, making preparations for public works projects, and officiating various ceremonies. On numerous holidays throughout the year, Isabelle appears in the town plaza, giving out holiday-themed items to players who speak with her.
Due to her characterization, Isabelle gained a considerable amount of popularity, to the point that she quickly became a mascot of the Animal Crossing series alongside long-time fan favorites Tom Nook and K.K. Slider. In regard to promotional material, the Animal Crossing series' official Twitter account was created to initially appear as Isabelle's personal account. Isabelle's popularity also resulted in her debuting as a playable character, albeit outside of her home series, in Mario Kart 8 via the Animal Crossing × Mario Kart 8 downloadable content pack.
In Animal Crossing: New Horizons, Isabelle is Tom Nook's assistant for Nook Inc. Unlike in New Leaf, the player must meet certain requirements in order for her to appear. Specifically, the player must help Timmy and Tommy establish a Nook's Cranny, invite three villagers to reside on their deserted island, and then complete a number of tasks issued by Tom Nook in order to make the island properly hospitable for the three invited villagers.
Upon meeting these criteria, Tom Nook will announce that Resident Services would undergo reconstruction. The day after construction is completed, Isabelle will join Nook during his daily island announcement, and proceeds to share the role of conducting civic duties with him at the renovated Resident Services. Isabelle maintains her service in evaluating the town and its residents, whereas Nook handles infrastructural work.
As an Assist Trophy
Isabelle appears as an Assist Trophy in Super Smash Bros. 4. When summoned, she will stay in place and toss healing fruit to whoever summoned her. While it is possible for opponents to intercept the fruit, only the summoner has the advantage of only having to touch the fruit to heal; opponents will have to actively grab them with the shield or attack buttons.
Isabelle cannot be attacked, though she will flinch if opponents get close. If the summoner is KO'd while she is still active, Isabelle will hunch over with a dismayed expression until the summoner returns. Conversely, she will cheer if the summoner scores a KO.
In Smash Tour
Isabelle also appears as an item in Smash Tour. When selected, all stat-boosting items near the player grow to their maximum size.
As a costume
Isabelle is the basis for a paid downloadable Mii Costume. Although the Isabelle Hat can be worn by any type of Mii Fighter, only Mii Gunners can wear the Isabelle Outfit. While worn, the Mii Gunner uses a Party Popper instead of their standard arm cannon.
Isabelle's standard trophy can be obtained in both versions of Super Smash Bros. 4, and in Super Smash Bros. for Wii U it is part of the Animal Crossing: New Leaf Trophy Box. However, the trophy of her wearing her winter attire is only available in Super Smash Bros. for Nintendo 3DS.
As a playable character
Main article: Isabelle (SSBU)
Isabelle appears as a newcomer in Super Smash Bros. Ultimate. She was revealed during the Nintendo Direct on September 13th, 2018 alongside a teaser for the then-unnamed Animal Crossing: New Horizons. Although Isabelle shares several moves with Villager, such as Pocket, the overwhelming majority of her respective versions have minute aesthetic and/or mechanical differences, such as her version of Balloon Trip. When coupled with her other moves being unique to her, her slightly different physique and her somewhat different attributes, Isabelle functions as a semi-clone of Villager.
As a costume
The Isabelle Mii Costume reappears, albeit as unlockable content instead of downloadable content.