Editing Super Smash Bros. Ultimate

An [[Inkling]] from the {{uv|Splatoon}} series, with various male and female designs from the original ''{{s|inkipedia|Splatoon}}'', was the first character confirmed to appear in the game as a new playable fighter in the base roster. [[Ridley]] (with [[Meta Ridley]] as an alternate costume) from the {{uv|Metroid}} series and [[Daisy]] from the {{uv|Mario}} series were confirmed to be playable during [[E3]] 2018. [[Simon Belmont]] and his descendent [[Richter Belmont|Richter]] from the {{uv|Castlevania}} series were announced as the game's first third-party newcomers in the August 8th, 2018 [[Nintendo Direct]]. [[King K. Rool]] from the {{uv|Donkey Kong}} series, [[Dark Samus]] from the {{uv|Metroid}} series, and [[Chrom]] from the {{uv|Fire Emblem}} series were all confirmed to be a playable newcomers as well during the same Nintendo Direct. [[Isabelle]] from the {{uv|Animal Crossing}} series, who previously appeared in ''Smash 4'' as an [[Assist Trophy]], makes her playable debut as the second ''Animal Crossing'' fighter. Finally, an [[Incineroar]] from ''{{s|bulbapedia|Pokémon Sun & Moon}}'' and [[Ken]] from the {{uv|Street Fighter}} series joins as the title's last base roster newcomers.  

In addition, most full [[clones]] and one semi-clone are now labeled as "Echo Fighters" and are marked with an epsilon (ε) next to their fighter numbers, which they share with the characters they are based on. Returning characters [[Lucina]] and [[Dark Pit]] are given this title (as they are Echo Fighters of [[Marth]] and [[Pit]], respectively), while new characters [[Princess Daisy]], Richter, [[Chrom]], [[Dark Samus]] and [[Ken Masters]] are Echo Fighters of [[Princess Peach|Peach]], Simon, [[Roy]], [[Samus]] and [[Ryu]], respectively. Aside from an option allowing these characters to be displayed on the same slot as their counterpart on the [[character selection screen]] exclusively during [[Vs. Mode]], [[Tourney]], [[Custom Smash]], [[Super Sudden Death]] and [[Quickplay]], there is no special distinction between most of them in-game and the name is used mostly for marketing purposes.

Twelve (or thirteen) characters were added to the game from January 2019 to October 2021 via downloadable content. The first of these, a [[Piranha Plant]] from the {{uv|Mario}} series, was released as an early purchase bonus DLC character. An additional five newcomers were added in Fighters Pass Vol. 1: [[Joker]] from the {{uv|Persona}} series, an amalgamation of several [[Hero]]es from the {{uv|Dragon Quest}} series, [[Banjo]] and [[Kazooie]] from [[Banjo-Kazooie (universe)|their namesake series]] (counting as one character), [[Terry Bogard]] from the {{uv|Fatal Fury}} series, and [[Byleth]] from {{uv|Fire Emblem|Fire Emblem: Three Houses}}. Following this, an additional six (or seven) characters were added in Fighters Pass Vol. 2: [[Min Min]] from {{uv|ARMS}}, [[Steve]] from the {{uv|Minecraft}} series, [[Sephiroth]], arch-nemesis of [[Cloud Strife]], [[Pyra]] and [[Mythra]] from {{uv|Xenoblade Chronicles|Xenoblade Chronicles 2}} (counting as one or two characters), [[Kazuya Mishima]] from the {{uv|Tekken}} series and [[Sora]] from the {{uv|Kingdom Hearts}} series.

As in ''Smash 4'', further "characters" exist as alternate costumes for preexisting characters. In this game, fourteen characters have such costumes: [[Alph]] is accessible as a playable character via [[Captain Olimar|Olimar]]'s [[alternate costume]]s; the seven [[Koopalings]] are available as playable characters via [[Bowser Jr.]]'s alternate costumes; one of [[Pichu]]'s costumes depicts the specific "Spiky-eared" variant; [[Alex]], a [[Zombie]] and an [[Enderman]] appear as Steve's alternate costumes; Pokémon Trainer, [[Wii Fit Trainer]], [[Robin]], [[Corrin]] and Byleth each have opposite-gendered variants as alternate costumes; [[Pikachu]] possesses both an opposite-gendered variant and a costume depicting the specific "Cosplay" Pikachu variant; each of [[Villager]]'s and Inkling's costumes represent different customization options for the character, including gender; the Hero has three other protagonists from across the ''Dragon Quest'' series as palette swaps; and the [[Ice Climbers]] swap the playable Ice Climber from Popo to Nana in half of their alternate costumes. Additionally, the [[Mii Fighter]]s have alternate gender options depending on the created Mii used for them. However, none of these characters are treated separately in-game.

Only the [[Fighter#"Perfect-attendance crew"|Original 8]] characters from ''[[Super Smash Bros.]]'' and any DLC fighters that have been purchased are available from the start. Like in ''Smash 4'', the Mii Fighters are also available via customization without needing to be unlocked traditionally but are still technically locked upon initial startup of the game. The rest of the cast must be unlocked; however, the unlocking process and conditions are much simpler than in past games. Fighters will challenge the player in ten-minute intervals after completing a basic activity, such as a battle or by clearing {{SSBU|Classic Mode}} with a prerequisite character, and can also be unlocked by being rescued in [[World of Light]], rather than having unique unlock criteria for each character.

With the exception of the ''Super Smash Bros.''-original stages, all stages are ordered chronologically like the fighters are, based on their first appearances in the series (excluding the stages that were introduced in both versions of ''SSB4'', which are listed among the stages introduced in the Wii U version). For the first time in the series, all stages are available immediately from the start, with none that need to be unlocked first. Additionally, due to [[8-Player Smash]] no longer being a separate mode from regular [[Versus Mode|Smash]], all stages can be played with up to eight players, rather than just a select few as in ''for Wii U''. All stages have both a [[Battlefield form]] and [[Ω form]]. In its base game, ''Ultimate'' features 103 stages (305 if counting Battlefield forms and Ω forms separately). There is an [[Training (stage)|additional stage exclusive to Training Mode]], which replaces the Random Stage option on the stage selection screen for said mode.

A year after the video, on October 30, 2023, Sakurai [https://www.youtube.com/watch?v=RDrNWAHaKfI uploaded a video] discussing about the game's development, such as how they managed the development of DLCs in privacy during [[COVID-19|the COVID-19 pandemic]], and when the proposal document was completed. Additional information that were not shown in the last video includes a VR mode in the document, years before the {{uvm|Nintendo Labo}} existed. In the end, he says he is unsure of the series' future, though there could be a next installment of the series with less content in general than ''Ultimate''. After being inactive for two years, new info were published on the internet in its fifth anniversary announcing the resume of maintenance for the game, with new events starting January 2024. Slightly earlier, Bandai Namco has also created [[Studio 2 & Studio S]]; a subsidiary company working with Nintendo, with the latter seemingly composed of the team who worked on the ''Super Smash Bros.'' series since ''Super Smash Bros. 4''. While active development on ''Ultimate'' has seemingly restarted since the introduction of these new events and patch updates being released for version 13.0, the scale of development and how long this period will last is currently unclear. After the release of the Sora amiibo and a small patch update, [[List of updates (SSBU)#13.0.2|version 13.0.2]], that adds support of the latter, Sakurai said his work for ''Ultimate'' is finally complete.<ref>{{cite web |url=https://www.ign.com/articles/masahiro-sakurai-says-his-work-on-super-smash-bros-ultimate-is-now-done |title=Masahiro Sakurai Says His Work on Super Smash Bros. Ultimate Is Now Done |publisher=IGN |author=Ryan Dinsdale |date=February 16, 2024 |accessdate=February 16, 2024 }}</ref>

''Ultimate'' adopts a {{iw|wikipedia|semantic versioning}} system (''major.minor.patch''), meaning each update is categorized based on its significance. Updates that introduce new fighters and their challenger pack change the first number (i.e. version 2.0.0). Otherwise significant updates such as new content or major game mode alterations that do not have any [[downloadable content]] attached change the second number (i.e. version 2.1.0). Smaller updates that exist solely to change the game in minor ways like character balance, bug fixes or [[amiibo]] support change the third number (i.e. version 2.1.1), though the latter two haven't always been applied consistently. When a number is changed, all numbers after it are reverted back to 0 (i.e. version 3.0.0). Compared to the simple incremental system used by ''Smash 4'', the semantic versioning used by ''Ultimate'' allows players to more easily infer the significance of any given update at a glance. The latest update for ''Ultimate'' is version [[List of updates (SSBU)#13.0.3|13.0.3]].

The game has sold 12.08 million units as of December 31st, 2018, marking it as the fastest-selling Nintendo game in history (at the time).<ref>{{cite web|url=https://www.vg247.com/2019/01/31/super-smash-bros-ultimate-is-the-fastest-selling-nintendo-game-ever/|title=Super Smash Bros. Ultimate is the fastest-selling Nintendo game ever}}</ref> In March 2019, that number reached 13.81 million, surpassing the total number of sales for the Wii U console in just 4 months. Since then, that number has reached 35.14 million units as of September 30, 2024<ref>{{cite web|url=https://www.nintendo.co.jp/ir/en/finance/software/index.html|title=IR Information:Top Selling Title Sales Unit|publisher=Nintendo|accessdate=2021-05-30}}</ref>, making it the best selling game in the series and the third best-selling game on the Nintendo Switch, and also making it the best selling fighting game of all time (previously held by ''[[Super Smash Bros. Brawl]]'' with 13.32 million copies). If all versions of a game are to be counted as a single entry, it would still be the best selling fighting game of all time (previously held by the combined sales of all versions of ''[[Street Fighter]] II'' with 15.5 million copies.)<ref>{{cite web|url=https://www.ign.com/articles/2019/11/04/super-smash-bros-ultimate-is-the-best-selling-fighting-game-ever/|title=Super Smash Bros. Ultimate Is The Best Selling Fighting Game Ever|publisher=IGN|accessdate=2020-11-14}}</ref> This success led to the game being displayed as one of the "Key Titles" in the Nintendo Switch section of the Nintendo Museum.<ref>{{cite web|url=https://www.youtube.com/watch?v=rtT75FM8zHM&t=1557|title=【◯◯◯万円!?】店のもの全部下さいって言ったら超大変なことになった…【ニンテンドーミュージアム】|publisher=YouTube|author=HikakinTV|date=October 2, 2024|accessdate=October 8, 2024|language=ja}}</ref>

''Ultimate'' continued the momentum of mainstream success started in ''Brawl'' and continued with the Wii U version, such as a mainstage presence at [[EVO]] and major tournaments dedicated to ''Ultimate'' often being the most watched events online, with ''Ultimate'' also frequently being the most entered tournament in a series with other games. The scene also weathered the [[COVID-19 pandemic and its impact on competitive Smash|2020 COVID-19 pandemic]] and led the charge in normalizing online play as a legitimate form of competition.