Sequel Number Snarl

"Kingdom Hearts III is the tenth game in the Kingdom Hearts series."^note It's potentially the eleventh.

—Mr. Feel

Not even Square Enix's guiltiest series.

A sequel number snarl often occurs when Sequels and Interquels start filling up the chronology, which then gets difficult to understand by the addition of a differently named work or two (or five...) whose titles don't include a number. Reboots, Alternate Continuities and even Market-Based Titles can make it even harder to understand. This is sometimes intentionally invoked if there's been a notable gap since the last one, like with Assassin's Creed III and Kingdom Hearts III. After all, if the number is there, it must be a big deal!

A Sub-Trope of Numbered Sequels. If the numbering doesn't start with 1, but is otherwise logical, see N+1 Sequel Title. If it's chapters within a single work that are numbered unusually, that's Unusual Chapter Numbers.

---

Examples:

• Video Games

Card Games

• Magic: The Gathering has a tradition of creating "Core Sets" which contain all the cards Wizards of the Coast to be in Standard^note The game's most popular "format", or "supercollection of cards you're allowed to play with at one time". Standard consists only of cards that have been printed in the past two years. Theoretically, it is therefore immune to Power Creep. (Realistically, it has just as many problems as the rest). Their first intentional Core Set was 4th Edition — which was the fifth basic set after Alpha, Beta, Unlimited and Revised, but was justified as being 4th by claiming that Alpha and Beta were halves of the same edition. 'Classic' 6th Edition was the first base set to use an expansion set symbol on the cards; prior sets were identified by print quality, border size/color and date. The sets were printed every two years, using ordinal numbering, until 2007's 10th edition (10E), which then shifted to Title by Year (and annual Core Sets) with Magic 2010 (M10), anticipating the year the same way car models do. M16 was renamed with the odd-man-out title of "Magic Origins," the Origins Episode for a continuous Plot Arc concerning the "Gatewatch," the game's Super Team, which lasted until 2019. During this time, there were no Core Sets. Afterwards, Wizards resumed them; M19, M20 and M21 were released as usual, but M22 will be replaced with a Dungeons & Dragons crossover set.

Comic Books

• The Incredible Hulk: The Incredible Hulk (1962) was originally canceled after six issues. After appearing in various other mags and becoming more popular, the Hulk was given a new solo feature in the Tales to Astonish anthology. When Marvel finally found a better distributor, the character became its own mag again with The Incredible Hulk (1968), but it neither started over with a new #1 nor did it continue the original numbering, it continued that of Tales of Astonish, with #102. This resulted in confusion over whether the revival should be considered a resumption of the original series or a second volume — Marvel's website uses the former interpretation while their trade collections prefer the latter.

Films — Live-Action

• In Italy, Dawn of the Dead was dubbed under the title of Zombi, spawning two unofficial sequels produced by Lucio Fulci (who was responsible for the Italian dub): Zombi 2 and Zombi 3D. In the U.S., Zombi 2 was retitled Zombie and marketed as a standalone movie with no ties to Dawn of the Dead, but Zombi 3 kept its original numbering, making it seemed as if there was another movie in-between. To add further confusion, two unrelated movies by Zombie 3 co-producer Claudio Fragasso were marketed as Zombie sequels in the U.S.: After Death (aka Zombie 4) and Killing Birds (a.k.a. Zombie 5). In the UK, all four of these movies were released under the title Zombie Flesh Eaters title and were numbered appropriately.
• The Halloween Films. The series is fairly straightforward at first, with Halloween, Halloween II, Halloween III: Season of the Witch, Halloween 4: The Return of Michael Myers, and Halloween 5: The Revenge of Michael Myers. Then things start to go off the rails with a sixth movie titled Halloween: The Curse of Michael Myers. Following that, we get Halloween H20: Twenty Years Later, an Alternate Continuity film that totally ignores the last three movies, and then a follow up to that film called Halloween: Resurrection. It then becomes really hard to keep track of things with the 2007 reboot Halloween directed by Rob Zombie, and the followup to that film Halloween II two years later. Then, finally, we got Halloween in 2018, which is a sequel to the Original Halloween that discards all the previous films in the franchise and was followed by Halloween Kills and Halloween Ends. So, all told, there are three films in the franchise simply titled "Halloween", two films titled "Halloween II" and a film titled "Halloween" that serves as a direct sequel to a movie titled "Halloween".
• The Hindi-language superhero film Krrish 3, the second film to feature Hrithik Roshan as Krishna Mehra/Krrish, is the sequel to Krrish, the first film about Krishna but the second film in a series began with Koi... Mil Gaya (Found Someone), starring the same actor as Rohit, Krishna's father (who also appears in the sequels).
• The Rambo series goes First Blood, Rambo: First Blood Part II, Rambo III, and then Rambo (also known as John Rambo or Rambo IV in certain countries) and finally Rambo: Last Blood. Film critic Roger Ebert pointed out that technically, Rambo III should have been entitled Rambo II: First Blood Part III, which, he supposed, would have caused film executives' heads to explode in confusion.
• The Ring:
  • A 1995 film, named Ring and re-released as Ring: Kanzenban.
  • Hideo Nakata series: Ring, Rasen, Ring 2, which ignores the events of Rasen, and a prequel Ring 0: Birthday.
  • American films The Ring, The Ring Two, and Rings (not to be confused to the short film included in the first movie's DVD).
  • Korean film The Ring Virus.

Literature

• The Alex Rider series consisted of nine books plus an unnumbered prequel. Then a reprint with new covers for the tenth anniversary marked the prequel as the tenth book in the series. Then author Anthony Horowitz decided to bring the series back, meaning the first new book was either the tenth or eleventh, depending on how you counted it, and indeed official promotional material for the book referred to it as both at different points. Then the next book was a short story collection consisting of a mixture of new and previously published material, so nobody is sure if that is the eleventh or twelfth or even if it should be unnumbered. The next "proper" book in the series, Nightshade, is thus the eleventh if you only count the main sequence, the twelfth if you include the prequel but not the short story collection (or vice versa), or the thirteenth if you include both.
• The Chronicles of Narnia started out in chronological order, but the fifth and sixth books published are respectively an interquel (set during the Time Skip at the end of the first book) and a prequel (set before any of the other books). More recent editions of the series number the books in chronological order, but many fans still maintain that reading them in publication order is more rewarding, because the prequel contains references that only make sense if you've read the other books first. As for C. S. Lewis himself, he had a slight preference for the chronological order, but he ultimately never really cared about the order in which people read his books.
• The books of Lorien Legacies. We present you (with the actual order in parentheses):
  • I Am Number Four (actually the first);
  • The Power of Six (actually the second);
  • The Rise of Nine (actually the third);
  • The Fall of Five (actually the fourth);
  • The Revenge of Seven (actually the fifth);
  • The Fate of Ten (actually the sixth);
  • United as One (actually the seventh; or the last). Over here, we've already lost it.
• The numbering of the books in the Relativity series is straightforward until you get to book 7. At that point, the storyline splits off in two directions, with the two different paths referred to as "Book 7" and "Book 7½". Also, the first book of side stories is logically called "Relativity Side Stories Book 1", but its original title was "Relativity Book 4½". For bonus confusion it was released one week prior to Book 4.

Live-Action TV

• Australian Survivor had two separate seasons in 2002 and 2006 by different networks that failed to be greenlit for follow-ups, before the 2016 revival on Network Ten became a massive hit that's been ongoing ever since. As a result, sources tend to go back and forth over whether the two pre-2016 seasons should be considered Season 1 and 2 of the ongoing Australian Survivor, or whether the current show is a separate entity that ignores what came before it.
• Doctor Who:
  • Season numbering can be quite confusing. Does the revival series start again, which means distinguishing between two Season Ones? (This is the official stance of The BBC, who classifies the classic series seasons as "seasons" and the revival series seasons as "series" - while still being at pains to point out that it's all the same TV show.) Or do you just keep going past Season 26, as many fans do? (This Very Wiki's Recap page lists both.) Steven Moffat confused things further by claiming in Doctor Who Magazine that if Matt Smith's first season wasn't Season 31 (because it's all one thing), then it was Series 1 (since it was as much a split from what had come before as the initial relaunch), before later admitting that he'd called it Series 5 in all practical situations. And then there's the split series 6A and 6B (Not to be confused with Season 6b) ... or season 32A and 32B.
  • Interestingly, this has been introduced in-universe with the Doctor themself. Originally, when regeneration was introduced, it wasn't stated that William Hartnell's character was in fact the First Doctor. The Fourth Doctor serial "The Brain of Morbius" has a scene alluding to prior regenerations. However, it was later firmly established in "The Five Doctors" that the First Doctor was the original incarnation, at least for now. Then came "The Name of the Doctor" and "The Day of the Doctor", which introduced a new incarnation between 8 and 9. It was stated that the Doctor doesn't consider the War Doctor to be worthy of the title, so he doesn't count in the numbering. Add in "The Time of the Doctor", which stated that Ten's aborted regeneration/half-human duplicate from "Journey's End" actually counted against the regeneration limit, and you have a situation where the Twelfth Doctor could technically be considered the Fourteenth. Then, after that, "The Timeless Children" stated that the Doctor had numerous incarnations prior to the First (with the ones from "The Brain of Morbius" specifically included) which had been wiped from their memory.
  • Played for laughs in a cinema prelude to Twelve's debut, where Strax notes that the numbering of Doctor gets "tricky" as you go on.
    Strax: The Eleventh Doctor... possibly the Twelfth. Technically, the Thirteenth! Who can say?
  • The Doctor themself gets around the whole business by counting personalities and regenerations separately. X Doctors, one incarnation who didn't claim the title, one extra regeneration burned. But it doesn't really matter, because the Doctor is the Doctor, no matter what face they're wearing.
• The Kamen Rider franchise has a similar issue as Super Sentai/Power Rangers below, not with the number of shows, but with the official number of "main character" Riders:
  • The first Kamen Rider series had two main Riders. Takeshi Hongo was orignally intended to be the only Rider on the show, until the actor portraying him (Hiroshi Fujioka) got injured in a stunt gone wrong. The character of Hayato Ichimonji (played by Takeshi Sasaki) was created to temporarily replace Hongo as Kamen Rider's new alter-ego (with a different suit to set him apart) until Fujioka recovered from his injuries. Once that happened, Hongo regained his protagonist status as Rider 1, but Ichimonji stuck around and still made guest appearances as Rider 2, thus the presence of two main characters for the same series.
  • The second series, Kamen Rider V3, featured a secondary character named Riderman, a villain who underwent a Heel–Face Turn. Despite the fact that Riderman was not a main character and was only around for a few episodes, he shows up in many of the subsequent crossover movies and specials, where he was counted as the fourth main Rider.
  • Kamen Rider Stronger, the seventh Rider (who starred in the fifth series), had a female sidekick named Tackle. Unlike Riderman though, she is not counted as an official Rider.
  • The main riders of the eighth and ninth series, Kamen Rider BLACK and Kamen Rider BLACK RX, were originally counted as one Rider since they were different alter-egos of protagonist Kotaro Minami (RX being an upgraded form of the original Black). Thus, RX was counted as the eleventh Rider when the older Riders guest-starred in his show. However, Black and RX were later counted as separate characters when RX guest-starred in a two-part episode of Kamen Rider Decade where he teamed up with an alternate universe version of himself who retained his original Black form.
  • There were also a bunch of Riders that never had their own TV shows. Kamen Rider ZX, the official tenth rider, was a character made for a series of photo stories in magazines and stage shows before getting his own TV special. Kamen Rider Shin (the 13th Rider, if we count Black and RX separately) was intended to be the protagonist of a series of adult-oriented video movies that never made it pass its first installment, while ZO and J (14th and 15th respectively) were also one-offs from different movies. It seems that Toei's official stance was that as long as a Rider was depicted in live-action, he counted as one.
  • All of the shows from Kamen Rider Agito and onward had numerous secondary Riders (including movie-exclusive characters) in addition to the titular protagonists^note For example, Kamen Rider Ryuki had 13 Riders (some of them villains), plus two pseudo-Riders who now will always attain upgraded forms later in their show without fail. Kamen Rider Decade established the producers' stance on who qualifies as a official main Rider: all of the Riders from the first series to Kamen Rider Kuuga with Black and RX cemented as two separate characters at this point, and then only the titular Riders from Agito onward counted as one character each, thereby protecting the Early-Installment Weirdness of both Riderman's main Rider status and the peculiar upgrade nature of Black and RX under a Grandfather Clause.
    • The official main Rider count leaves out Kamen Rider: The First, Kamen Rider: The Next and Kamen Rider Amazons ("the Showa Riders born in the Heisei era" as Kamen Rider Zi-O's canonical final stage play named them - the first two being a Continuity Reboot of the first series and V3, and the last one an adult-orientated Bloodier and Gorier extremely loose re-imagining of Kamen Rider Amazon), as well as Kamen Rider G (a Rider created for a one-off parody).
• Power Rangers:
  • Mighty Morphin' Alien Rangers, a transitional period between the third season of Mighty Morphin' Power Rangers and Power Rangers Zeo. It's commonly considered Season 3b, being too short to be a season in itself and sharing enough with Mighty Morphin' S3 to be lumped in with it.
  • Years later, part of the first season was Re-Cut and presented as a new season in itself. Officially, it was Season 18, but fans were reluctant to name glorified reruns as a full season and generally considered the following span of new episodes, Power Rangers Samurai, as the actual Season 18. Within a few years, official sources followed suit and ignored the Re-Cut in official season counts.
  • Beginning with Power Rangers Samurai, franchise installments began being stretched over two years, with the second year of each having an updated New Season, New Name, leaving fans unsure whether to count each as one two-year season or two one-year seasons. Power Rangers Megaforce complicates things further since each of its two years adapts a different Super Sentai series while the others adapt just one series for the duration. While Saban remained hush-hush on the subject, the franchise's next owner Hasbro settled for two one-year seasons as their official stance, naming 2021's Power Rangers Dino Fury the 28th season in its teaser trailer.
• Super Sentai itself also underwent a similar situation. The first two Sentai shows, Himitsu Sentai Gorenger and J.A.K.Q. Dengekitai, which Toei co-produced with Ishinomori Production, were not counted among the later Super Sentai shows that Toei produced independently starting with Battle Fever J. As a result, the premiere of Kousoku Sentai Turboranger served as the tenth anniversary of the franchise, while Gosei Sentai Dairanger was originally considered the fifteenth series. But during the production of Chouriki Sentai Ohranger, Goranger and J.A.K.Q. were retroactively added to the franchise's count in order to make Ohranger (which aired in 1995) the 20th anniversary show.

Music

• Chickenfoot's second album is Chickenfoot III to spoof Sophomore Slump.
• The original 1984 version of "Do They Know It's Christmas?" was performed by a Super Group named Band Aid. A cover was made in 1989, whose supergroup was called Band Aid II. However, when a second cover was made in 2004, the supergroup was called Band Aid 20.
• Korn's 2010 Revisiting the Roots album, Korn III: Remember Who You Are, is their ninth album but the third with producer Ross Robinson, who produced their first two albums.
• The debut solo album of Paul McCartney, McCartney (1970), was followed years later by McCartney II (1980) and McCartney III (2020), despite his having released many other albums in between. The three are connected not through sequential order, but by the circumstances of their production: McCartney recorded each album in his own home, playing every instrument, and acting as his own producer, in essence making them truly solo efforts.
• Santana's Santana IV is their twenty-fourth album but the fourth with most of their Woodstock-era lineup, which recorded the first three.
• The Traveling Wilburys named their first album Traveling Wilburys Vol. 1, and their second album Traveling Wilburys Vol. 3 — either as a joke, or to reference their involvement in the charity album Nobody's Child: Romanian Angel Appeal, which featured a track by the Wilburys, as well as two George Harrison songs, as a supposed Vol. 2.
• While Van Halen II is a Chronological Album Title, Van Halen III is the band's eleventh album, so named because it marked their third singer.

Software

• Microsoft Windows. Internal and external version numbers haven't matched in years. Part of this complexity stems from the different versions being entirely different code bases over the years. Earlier versions were based on the old MS-DOS system (indeed, Windows was originally an add-on program to DOS, not an operating system). This applies to every version up to and including the 95/98/Me versions (DOS-based Windows 4.x, internally). Meanwhile, the NT code base was introduced as a high-end, network-friendly system, released in parallel and aimed at businesses.
  • Consumer versions started off with straightforward ordinal numbers: 1.0, 2.0, 2.1, 3.0 and then 3.1 in 1992, the version where it really got popular. Meanwhile, the first version of Windows NT was NT 3.1 (the same version number DOS-based Windows was on at the time; the user interface of NT 3.1 looked and functioned just like the DOS version).
  • Then the consumer version shifted to Title by Year: Windows 4.0 was instead "Windows 95," followed by Windows 4.1 / Windows 98 three years later. Meanwhile, Windows NT 4.0 was released at the same time as Win 95 (and looked just like it, despite not being internally compatible).
  • In the year 2000, Windows NT shifted to Title By Year too: Windows NT 5.0 was released as Windows 2000 Professional (and Windows 2000 Server). As a result, the next consumer Windows was released as Windows Millennium Edition (or "Windows Me") instead of with a year. Internally, it's numbered 4.9.
  • The consumer and NT branches were finally unified in Windows NT 5.1, released in 2001 as Windows XP. As a result, WinXP was also the first to come in "Home" or "Professional" flavors, a distinction that continues to exist today. 18 months later, the Server edition was released as Windows Server 2003.
  • Windows NT 6.0 (released at the turn of 2007) introduced another new naming scheme by taking the name "Windows Vista". A year later, the Server edition was released as Windows Server 2008. However, Vista was poorly received, which may have prompted the new naming scheme of its successor: Windows NT 6.1, released as "Windows 7" (and accompanied by Windows Server 2008 R2). Following in these footsteps, Windows NT 6.2 was released as "Windows 8" (with Windows Server 2012) and Windows NT 6.3 was released as "Windows 8.1" (with Windows Server 2012 R2).
  • The 2015 release of Windows jumped a bunch of numbers, becoming ver. 10.0 and Windows 10 (with Windows Server 2016) instead of the obvious "Windows 9"... because naming it that would cause a Continuity Snarl where programs would confuse it for Windows 95 or 98. As of 2020 subsequent releases are still "Windows 10", with a YYMM version number added to the "public" name (e.g Windows 10 version 2004 for Windows v10.0.19041.xxx).
  • Finally, 2021 saw the release of Windows 11; however, internally it's still version 10.x.

Tabletop Games

• The various Dungeons & Dragons editions are titled Dungeons & Dragons, Dungeons & Dragons Basic Set, Advanced Dungeons & Dragons, Advanced Dungeons & Dragons 2nd Edition, Dungeons & Dragons 3rd Edition, Dungeons & Dragons v3.5 (a minor revision), Dungeons & Dragons 4th Edition (plus its Retool Essentials, which isn't counted as a new edition), and Dungeons & Dragons 5th Edition. While the relationships between early versions isn't hard and fast (they were considered the same game, just aimed at different audiences, and were largely compatible until the Basic Set was revised in 1981), there's no way 5th Edition is actually the 5th version of the game.
• The RPG RuneQuest was originally published by Chaosium in 1978. A slightly revised 2nd edition was published not too long after. An expanded 3rd edition was released in 1983, developed by Chaosium but published by Avalon Hill as part of a deal that gave AH ownership of the name (an aspect of the deal everyone later said was a big mistake). So far straightforward, as each edition was just numbered, and fans and creators called them RQ1, RQ2, and RQ3 respectively.
  
  Then things went off the rails, as Avalon Hill mismanaged the line, and the game went stagnant for some years, as Chaosium didn't have the rights to the name anymore to make a new edition. Eventually Chaosium founder Greg Stafford left management of the company, taking the rights to the Glorantha setting (which he created) with him. Stafford, not Chaosium, was the one to reacquire the RuneQuest name from Avalon Hill (which had been itself bought by Hasbro). He licensed the name to Mongoose Publishing, which finally released a new edition, simply titled RuneQuest like prior editions, in 2006, though they couldn't use the previous texts as a base, as Chaosium still owned that, and had to rewrite it as close to the previous editions as they could. When a revised edition was released four years later, Mongoose titled it RuneQuest II, not to be confused with the actual second edition from the early 80s. These became known as "MRQI" and "MRQII", respectively. Mongoose lost the license just a year later, but the lead authors ofMRQII picked it up and through a new company released a 6th edition, RQ6 for short, which was really just a director's cut of MRQII.
  
  Re-enter Chaosium. Or more accurately, re-enter Greg Stafford to Chaosium. Although he had left management of it years before, Stafford still was a major owner of the company, and when it ran into financial trouble, he re-took control, which reunited RuneQuest with its original publisher. A new edition was announced (despite the relative newness of the 6th edition). During development they initially referred to it as "RQ4", as it's the fourth edition written by Chaosium, but it's the seventh overall (and ignoring the editions between was seen as something of an insult to their authors), so they dropped that. The full title of the new edition is RuneQuest: Roleplaying in Glorantha, which they abbreviate as "RQG". Just so happens that "G" is the 7th letter of the alphabet, so at least it's the right position. So the whole edition order goes: RQ1, RQ2, RQ3, MRQI, MRQII, RQ6, RQG.
• Traveller has this problem too. Original Traveller (1), MegaTraveller (2), Traveller the New Era (3), and then Marc Miller's Traveller aka Traveller 4th Edition or T4 are in an easy to understand, logical order. But T4 was followed by a slew of licensed editions that used the Traveller background with different rules sets: in chronological order GURPS Traveller (5), Traveller d20 aka T20 (6), and Hero Traveller (7). Then we had a licensed edition produced by Mongoose Publishing that was a revision of the original version's game mechanics called simply Traveller aka Mongoose Traveller(8) produced at the same time as Traveller 5th Edition (9) which was published by Marc Miller, the original creator of Traveller, and was an update of the 4th edition rules. To muddy things further, Mongoose has now produced a second edition of their rules (also called Traveller but sometimes referred to as Mongoose Traveller 2nd Edition (10)), and is now producing a lightly-revised version of that called Traveller Update 2022 that might rightly be called the 11th version of this game.

Theatre

• The Tsukipro franchise has over 30 stage plays across 5 series — the series are divided by which of the Universal-Adaptor Cast's Geodesic units are the main characters. There are also numbered series by which world of The Multiverse they take place in. So, Tsukino Empire: Unleash Your Mind is the eighth installment of the Tsukiuta series, while Tsukino Empire 2: Beginning of the World is SQS episode 4. There is also Tsukipro Stage: Machine Elements eins: Sora wo Wataru Kaze and SQS episode 6: Machine Elements zwei: Akai Hono. The Tsukino Hyakki Yakou series aren't numbered, and they take place over a much longer time span...

Visual Novels

• Danganronpa: There are two entries with "3" in the title: Danganronpa 3 follows up on the story set in Danganronpa: Trigger Happy Havoc and Danganronpa 2: Goodbye Despair, but is an anime. Though Danganronpa V3: Killing Harmony is the third cardinal visual novel, it's the fourth video game overall counting the action spin-off Danganronpa Another Episode: Ultra Despair Girls as part of the games. It's also advertised as the first game in the Gifted Inmates Saga. This doesn't get into the unnumbered spin-offs and prequels meant to suppliment the Hope's Peak Saga, which sets both games labeled "3" much further down the line.

Web Original

• Discussed in The Angry Video Game Nerd's video "Chronologically Confused about Movie and Video Game Sequels." Also served as the basis for an episode of sister series You Know What's Bullshit?.

Western Animation

• The Super Mario Bros. Super Show! covers the first two Super Mario games, and was followed by the King Koopa's Kool Kartoons spin-off. The Adventures of Super Mario Bros. 3 is the second Super Mario cartoon, based on Super Mario Bros. 3. Super Mario World is the third cartoon, based on the fourth game.

Other

• Apple:
  • Apple's iPhone. First we have the original iPhone, which is followed by the iPhone 3G, named so because of its 3G network capabilities, but leading to confusion as to where the iPhone 2G went. (Answer: The original iPhone ran on 2G networks, so "iPhone 2G" became a working Fan Nickname for it.) The iPhone 3G was followed by the iPhone 3GS, a phone nearly identical to the iPhone 3G in terms of design, but with a better camera and processor (the "S" stands for speed.). Logically, a lot of people thought the next iPhone would run on 4G networks, and thus would be called the 4G. The next iPhone did not have such functionality, though. Instead, it was named the iPhone 4, since it was the fourth generation iPhone Apple produced. Logically again, people inferred that the next iPhone would be called the iPhone 5. Wrong again! It's the iPhone 4S, still without 4G capabilities (unless you count AT&T's experimental HSPA+ as 4G). It also established that Apple didn't consider "S" models to be a new generation, meaning the iPhone 4 really should have been the iPhone 3, but that would probably have been confusing following the 3GS. Apple's next phone (at long last, with 4G LTE capabilities) was then named the iPhone 5... despite being Apple's sixth-generation iPhone. Apple appeared to have settled into a comparatively sane pattern by following iPhone 5 with 5S (along with 5C), 6 and 6 Plus (a phablet model), 6S and 6S Plus, and 7 and 7 Plus. This trope comes back in full force in the eleventh-generation lineup: the iPhone 8, the iPhone 8 Plus, and the iPhone X (pronounced "iPhone ten")—named for the tenth anniversary of the original iPhone. These were followed by the iPhone XS, XS Max (what used to be called "Plus") and XR, the budget-minded member of the family; the old "Speed" designation can still apply, but Apple have confirmed that they are not supposed to, and that XR very specifically means nothing. Finally, the iPhone 11 (replacing the XR), 11 Pro (replacing the XS) and Pro Plus (replacing the XS Max) were announced in September 2019... followed by the 12, 12 Mini, 12 Pro and 12 Pro Max, skipping the entire "S" generation once again.
  • Apple's operating systems have some odd numbering methodologies too. iOS, originally iPhoneOS, has progressed normally from version 1.0 onward, though when they started basing other operating systems on it, namely tvOS and iPadOS, they started with versions 9.0 and 13.0 respectively, so all the version numbers would match. Meanwhile, macOS (formerly Mac OS X and OS X) has been at version 10 since 2001, with new versions given 10.x designations, mainly because the X (Roman numeral ten) was a large part of the brand identity until 2016, but it stayed at version 10 even after the X branding was dropped, until 2020 when Apple finally incremented the major version number to 11 with macOS Big Sur.
• Samsung Galaxy smartphones look positively sedate in comparison to Apple. Their first flagship phone, the Galaxy S, launched in 2010, with the Galaxy S2 following in 2011 and so on. In 2020, Samsung incremented the Galaxy S11 to the Galaxy S20, officially switching from ordinal numbers to Title by Year. (This partially makes up for their Kitchen Sink Included level of variety — the Galaxy A, the Galaxy J, the Tab, the Note which introduced the "phablet" style, the M — all of which have their own numbering schemes, and some of which repeat: there have, for instance, been two Galaxy A9s, which are differentiated solely by model year, as well as an A40, an A90, and eventually an A71.) Finally, there were rumors that the Galaxy S21 would actually be called the Galaxy S30, abandoning the "Title By Year" scheme after a mere one model year for something catchier; while these rumors turned out to be false, the fact that they gained traction at all speaks volumes.
• Sony's Xperia smartphone line has been absolutely chaotic. Aside from being named "Xperia," there's nothing in common. Its first year of models was a veritable kitchen sink of letters and names, until they finally settled on an Xperia Z1 flagship in 2013. This incremented by year for five years before Sony gave up and went back to Word Salad Titles in the form of the Xperia XZ, which was followed by the XZ1 (yes seriously), XZ2 and XZ3... until Sony gave up and rebooted their flagship lines with the Xperia 1 in 2019. Naturally, this was followed by the Xperia 1 II — yes, 1 in Arabic, 2 in Roman — in 2020, and the Xperia 1 III in '21. (The 1 is also augmented by the Xperia 5 "compact" and Xperia 10 "mid-range" models, which also use Roman ordinals.)
• OnePlus, an upstart phone maker from China, has had some similar bobbles. It has gone through 9 ordinal numbers, albeit skipping the OnePlus 4 model because Four Is Death, but has augmented this with T models ("OnePlus 6T") starting with the 5, which some snide commentators have taken as a display of dominance over Apple (since T is the next letter over S).
• Nvidia's GeForce series of graphic processors starts with the GeForce 256 and then goes 2-4, FX, 6-9 before switching to hundred numbers (e.g. 100, 200, 300) and then to tens with the current GeForce 10 and the upcoming GeForce 20.
• Over almost two millennia, papal numbering has had some hiccups:
  • Despite there having been only 21 legitimate Popes John (as of 2022), the most recent was numbered John XXIII, because John XVI was an antipope and there was no John XX. The numbering erroneously skipped from John XIX to John XXI.
    • Ironically, the reason there was not John XX was an attempt to avert this. At some point, someone in the Vatican read the Liber Pontificalis, a collection of biographies of past Popes. In it, John XIV is mentioned to have reigned for eight months then been imprisoned by an antipope for four months. However, due to how it was written^note "John, eight months", "John, four months", it was mistakenly believed to have said that there was a John XIV who reigned for eight months, then a second John XIV right after him who reigned for four. The imaginary second John XIV was then mistakenly conflated with a cardinal named John, who opposed the antipope that had imprisoned John XIV. Thinking that there had been a mistake and that Popes John XV to XIX had forgotten to count the second (nonexistent) Pope John XIV, Pedro Julião would take the name John XXI. Meaning that part of why the numbering was thrown off was because someone thought the numbering was off.
  • Aside from John XVI, other antipopes counted in the numbering are Alexander V, Benedict X, Boniface VII, and Felix II.
  • There was no Martin II or III, as the names Martin(us) and Marinus were conflated.
  • In 752, a priest from Rome named Stephen was elected to become pope, and would have been the second pope with that name, but died suddenly of a stroke a couple of days later before being fully installed. Confusion exists as to whether he counts as a pope, and with it the numbering of subsequent popes named Stephen, who are either Stephen II—IX or III—X, depending on the interpretation; that numbering didn't become common until the 10th century, after most of these popes had come and gone, doesn't help. Many sources would list both numbers, e.g. "Stephen III (IV)".
• Every wrestling fan know that Ric Flair is touted as a 16 time world champion by the WWE. However, this is not actually true, as he has held more than 16 world titles, but the exact number varies, sometimes up to 25. He himself, however, considers himself a 21 time world champion. His reigns include:
  • 12 NWA World Heavyweight Championships (3 of which, however, are considered unofficial. Only 8 of these title reigns are recognized by WWE).
  • 8 WCW World Heavyweight Championships (Only 6 are counted by WWE).
  • 2 WWE/F World Championships (both counted).
  • And 2 WCW International World Heavyweight Championships (neither of which are counted).

---