The game uses the traditional "falling notes" style of gameplay. Notes scroll down the gameplay lanes and for each note, the player must hit the corresponding part of the "Ground Slider" controller. Tap notes require the note to simply be tapped, Hold notes require holding down the necessary part of the slider until the note ends, Slide notes are similar to Hold notes but the player must drag horizontally along the slider, and Flick notes require the player to slide across the part of the slider corresponding to the note.
However, there's a unique twist to this formula: In addition to all of these, there are also Air notes, where the player must physically lift their hands off of the slider and wave them through a sensor above the slider; some Air notes simply require the player to tap the note and then lift their hand off into the sensor range, others require the player to keep their hand in the air afterwards to hit the mid-air "Air-Action" notes, and some other Air notes have the player move their hands down through the sensor to hit notes on the slider.
Notes need not be fixed-width like in many other rhythm games; each note can be as little as 1/16th as wide as the playing field, or as wide as the entire playfield, so depending on the note you have some leeway in how precise you have to be to hit it.
It is currently one of the most popular rhythm games in Japan, having surpassed DanceDanceRevolution in commercial success there and often competing with beatmania IIDX on that same metric, despite Sega only having about half as much time in the arcade rhythm game scene as Konami. It was originally a Japan-only game, but high demand outside of Japan led to SEGA producing a separate line of releases for the Asia Pacific / Oceania region.
In 2021, a "Gold" version of the CHUNITHM cabinet was released, with CHUNITHM NEW being the first game to be released for it (in addition to an upgrade kit for the older "Silver" version). The Gold cabinet comes with a 120 Hz monitor as opposed to the older "Silver" cabinet's 60 Hz monitor, and compatibility with Japanese e-payment systems but otherwise has the same functionality. The Japanese arcade chain Round 1 would then send its Silver cabinets to its US branches, all running CHUNITHM PARADISE LOST with all net features disabled and only a portion of the songlist available.
Compare Deemo, which shares a few common interface elements such as the variable-width notes, Arcaea which borrows the "air notes" concept, Nostalgia (BEMANI) which some have described as "Chunithm except with piano music", BanG Dream! Girls Band Party! which has been called "Chunithm but with idol bands" by some players, Tokyo 7th Sisters and Project SEKAI, both of which effectively port Chunithm mechanics onto the mobile screen (since the November 2017 update for the former), and Dance Rush which has been described as Chunithm EXCEPT WITH YOUR FEET!
Games in the series:
Japanese releasesClassic Chunithm games (Silver Model cabinet only)
- CHUNITHM (2015)
- CHUNITHM PLUS (2016)
- CHUNITHM AIR (2016)
- CHUNITHM AIR PLUS (2017)
- CHUNITHM STAR (2017)
- CHUNITHM STAR PLUS (2018)
- CHUNITHM AMAZON (2018)
- CHUNITHM AMAZON PLUS (2019)
- CHUNITHM CRYSTAL (2019)
- CHUNITHM CRYSTAL PLUS (2020)
- CHUNITHM PARADISE (2021)
- CHUNITHM PARADISE LOST (2021) — offline cabinets without licensed content can be found at some Round 1 USA locations
- CHUNITHM NEW (2021)
- CHUNITHM NEW PLUS (2022)
- CHUNITHM SUN (2022)
- CHUNITHM SUN PLUS (2023) — current version
Asia/Oceania Pacific releases (all using Silver Model cabinet)note
- CHUNITHM SUPER STAR (2020) note
- CHUNITHM SUPER STAR+ (2021)
- CHUNITHM NEW (2022)
- CHUNITHM NEW PLUS (2022)
- CHUNITHM SUN (2023)
- CHUNITHM SUN PLUS (2023) — current version
- 中二节奏NEW!! (2022) — current version
The CHUNITHM series provides examples of the following:
- All or Nothing: ExTap and Slide notes can only be rated Justice Critical or Miss, skipping Attack and Justice entirely. Downplayed, in that this is because the Justice Critical window overrides the Attack and Justice windows; so long as you hit them at all, you'll get a JC.
- Bullet Hell: Some World's End charts have the player holding one long note throughout the entire chart and trying to dodge damage notes on the track.
- Call a Hit Point a "Smeerp": The highest three judge ranks: Justice Critical (perfect), Justice (great), and Attack (good). Only the Miss judgement is Exactly What It Says on the Tin.
- Color-Coded for Your Convenience: Tap notes are pink, ExTap notes are glowing yellow, Hold notes have yellow tips and yellow-and-purple fills, Slide notes have blue tips with purple-and-cyan fills, Flick notes are blue, upward Air notes have green arrows, Air-Action notes are hot pink, and downward Air notes have pink arrows. During certain WORLD'S END charts, Damage notes are purple.
- Death Is a Slap on the Wrist: Failing a song only impacts clear status, gaining currency, all types of EXP, and Map progress, and does not impact your score, rank (which is tied to score), or Rating, unless you had a Sudden Death or Track Skip feature active. Furthermore, you will always get a full set of stages even if you fail all of them, except in Courses where failing ends the song and omits any remaining songs.
- Flawless Victory: Clearing a chart with only Justice or Justice Critical judgements results in a congratulatory "ALL JUSTICE!" message. The usual "Full Combo" is here, as well, if you get at least one Attack.
- Game-Breaking Bug: The international version of NEW has TEN FRAMES (or 1/6 second) of input lag.
- Gimmick Level: The WORLD'S END charts. In place of a difficulty number, each of these charts has a kanji corresponding to the type of gimmick it dominantly uses, with a star rating signifying the complexity of said gimmick. Due to the wide range of difficulties and weirdness these charts give, you only need to attain two clear marks to clear the song, and they won't affect your rating.
- 撃 "Strike" - Read as "geki", charts that emulate or are imported from O.N.G.E.K.I..
- 光 "Light" - Swaps out the regular notes with EX Notes.
- 避 "Avoid" - Chart contains electric blue damaging notes that must not be touched. A famous example is the last stretch of Cirno's Perfect Math Class, which throws a flood of these for you to dodge like danmaku.
- 止 "Stop" - The chart stops in set places.
- 戻 "Return" - The chart rewinds in places.
- 敷 "Spread" - Hold and Slide notes will expand to occasionally fill the entire lane, forcing you to keep a finger down on the slider while tapping notes at the same time.
- 跳 "Jump" - Replaces regular notes with Air and Air-Action notes,
- 両 "Both" - The chart is two half-sized charts, split down the middle.
- 割 "Split" - Wide notes are divided into smaller notes that fill its original width, adding extra precision.
- 狂 "Crazy" - Self-explanatory charts that are even harder than Master.
- 布 "Cloth" - Derived from "towel spinning" culture, where people spun towels like a helicopter to the beat of music. Flick, Air, and Air-Action notes are strung in a way that emulates a spinning motion. A demonstration of a Cloth chart can be seen here.
- 覚 "Memorize" - Requires memorization of patterns at certain points.
- 改 "Revise" - Alternative charts that still follow the balance of a standard chart, though still features some WORLD'S END-exclusive gimmicks.
- 蔵 "Warehouse" - Early versions of charts that got shelved during development.
- 招 "Invite" - Charts imported from another game entirely, such as Two-faced Lovers mirroring the note chart from Hatsune Miku: Project DIVA.
- 舞 "Dance" - Read as "mai", charts that emulate maimai.
- 弾 "Bullet" - Regular notes are replaced with flick notes.
- 時 "Time" - The song's BPM shifts at set points.
- 歌 "Song" - The notes are timed to the lyrics of the song.
- 速 "Speed" - Chart scroll speed changes or are very fast.
- 半 "Half" - The chart is compressed to fit half the play space.
- 嘘 "Lie" - Special April Fools' Day charts that are usually parodies of existing songs.
- 謎 "Mystery" - A secret chart hidden behind a puzzle, used solely by one song.
- ! and ? doesn't explain itself cleanly, as it's a thematic mashup of gimmicks by the note designer. "!" charts tend to be undefined in nature or involve dodging damaging notes on a set path, and "?" charts tend to encompass multiple clear gimmicks or irregular note speeds.
- Hard Mode Perks: Some skills award a significant boost to gauge gain, but activate Sudden Death if too many of a particular judgement or worse are obtained.
- Harder Than Hard: The difficulties go Basic, Advanced, Expert, and Master. CHUNITHM NEW adds a new ULTIMA difficulty, in a similar vein to RE:MASTER songs in the maimai series.
- Lighter and Softer: Whereas the original game and its PLUS version primarily use black and gold as its dominant colors, CHUNITHM AIR and its respective PLUS version use a sky theme with lots of turquoise and purple.
- Non-Standard Game Over:
- Certain skills, usually ones that award a substantial amount of gauge, will end the song prematurely upon meeting a specific condition, usually getting too many Misses, Attacks, or non-Critical Justices.
- The optional Track Skip modifier will end the song early if a player-set score target (grades starting from S or their personal best) is no longer possible to achieve.
- Portmanteau: The title is one on the words "chuunibyou" and "rhythm", or "tune" and "rhythm". This was confirmed in an interview by Japanese game publication 4Gamer
- Rank Inflation:
- The ranks go D, C, B, BB, BBB, A, AA, AAA, S, SS, SSS.
- Scores seem to be out of 1 million points, however, it is possible to go slightly over a million, and in fact, you need a little more than 1 million (1,007,500) for an SSS. This is because while a Justice gives 100% of the "maximum" note score, a Justice Critical gives you 101%.note
Just to emphasize the inflation, the Justice Critical judgement isn't even particularly hard to get by arcade rhythm game standards, as the timing window for it is ±33 milliseconds, the same as "perfect" judgements in many other rhythm games.To compare A 95% score in most other rhythm games means the player did well, while here, 950,000 is actually considered only an average score.
- Required Spinoff Crossover: Several songs from maimai and O.N.G.E.K.I. make their appearance here, and in return, songs from CHUNITHM cross over there.
- Scoring Points: Scoring is based strictly on accuracy. Getting a Justice gets you 100% of the note score, getting a Justice Critical gets you 101%, Attack gets you 50%, and a Miss gets you nothing. Hold and Slide notes are each counted as multiple notes. The score is based around 1,000,000 being a 100% score, with 1,010,000 as the actual maximum score obtainable.
- Socialization Bonus: Cabinet-to-Cabinet Play is a feature that lets players on linked cabinets play the same song together. Both/all players contribute to a shared "Chain" counter that basically functions as team-wide combo, and there are bonuses for reaching Chain milestones as well as achieving a Full Chain (a Full Combo from all players). Finally, all participants in a Cabinet-to-Cabinet round will be eligable for a fourth song in their credit (even if they only play one song as C2C).
- Some Dexterity Required: Some patterns involving Hold or Slide notes are best done by crossing your arms.
- Subverted: you don't have cross your arms, you can bring your hands together and then move them apart and it'll still count. Double subverted if one hand is dealing with Hold/Slide notes and the other is dealing with Air-Action notes.
- Too Long; Didn't Dub: SUPER STAR is mostly translated into English, however Character Skill descriptions either only have partial translations alongside the original Japanese text, while Skill names and other Skills' descriptions have no translation at all; song titles, artist names, and chart designer names are also left untranslated and unromanized. Starting from CHUNITHM NEW, Skill descriptions are all translated, but Skill names and song metadata are left in Japanese.
- Unwinnable by Design: You need to fill the gauge a certain number of times in order to clear the song, and the number of gauges you need to fill depends on the map among other conditions. It can happen that you are unable to fill enough gauges to clear the song, even if you get a perfect score; you also need the right Characters and Skills to be able to meet certain clear conditions. That said, Death Is a Slap on the Wrist; clear/fail only matters for map progression and unless you are playing in course mode, you will always get a full set of stages even if you fail all of them.