Simply put: If you can't get into tempai, it doesn't matter how many points your hand is worth. Double riichi - Chantaiyao - Sanshoku doujun - Ikkitsuukan - Toitoi - Sanankou - Sanshoku doukou - Sankantsu - Chiitoitsu - Honroutou. Em outras notícias, quero um set de riichi mahjong. Unlike the other yakuman patterns, the name "kazoe yakuman" is a generic name. Daisharin 「大車輪」 is one of three yakuman awarded for a closed hand with the following pattern: 22334455667788. tldr: For quick wins, get a dragon or seat/round wind triplet or dump all your terminals and honors. New (English) Riichi Mahjong Strategy Book. There are few characteristics of the common bully that separate it from other species. tanyao, toitoi, chanta, honitsu, pinfu (closed only) and chiitoitsu. Most beginners force Toitoi with a Chiitoi hand anyway. e. Thousands of new, high-quality pictures added every day. The winning hand also resembles the chiitoitsu or toitoi hands. . translated by anon Introduction This is a translation of a html book by Fukuchi-pro, author of 現代麻雀技術論 (Modern Mahjong Strategy Theory). Strategy: Go for chiitoitsu. Do you want to improve your skills in riichi mahjong, the popular Japanese version of the classic tile game? If so, you might want to check out this PDF file by Feng, a mahjong expert and instructor. If the hand is only toitoi (usually 2600 points as non-dealer) then the low value often doesn’t justify the slow speed and high risk of opening the hand to call tiles, and. Normally translated as a "half flush", this yaku features a hand composed only of honor tiles and tiles of a single suit. Notable people with the name include: Reiichi Ikegami (池上 礼一) (born 1983), Japanese footballer. You see it far less in higher level play just because it takes a long time to form. Dicionário . Western Classical Mah Jong. Fortunately, due to its popularity, there are numerous guides available to help you navigate the menus (just do a quick search to find them). (Pure Terminal or Honor), and Toitoi (All Pungs). Kan「カン」 is a special tile call in the game. (i. This yaku may apply to any closed hand and may be declared upon achieving tenpai. Chanta with toitoi or chiitoitsu actually forms honroutou instead of chanta, while chanta with chinitsu is actually junchan instead of chanta. Let‘s geek out and dive into some fascinating data! Given 4 sets of tiles with 34 types each, here are the probabilities of achieving key yaku hands: Riichi – 30-40%. Otherwise, the unwanted rinshanpai may be discarded and riichi be called. net. This is especially true for dealer Riichis. The toitoi is a small fish reaching an average size of 50-60 mm. Hard. A hand with 2 han and 110 fu is also possible, as in the following for the East player in the East round: Tsumo: 2 han from sankantsu; base fu: 20; tsumo: 2; pair wait: 2; composition of hand:you retard, a toitoi riichi is the strongest hand of all! four pairs, with a dora. Toitoi: A player wins with a hand consisting of only triplets (except the necessary pair). 副露. This is a high quality numbered american set that you can perfectly use for riichi. 24 Apr 2023 02:04:24Hmm. In Japanese mahjong, yaku ( Japanese: 役) is a condition that determines the value of the player's hand. Auto rotate discard tiles. Both those aiming for toitoi and those aiming for chiitoitsu discarded fewer yakuhai in early game, but in the toitoi case, yakuhai came spilling out in late game when they couldn’t be incorporated into the hand. I think we already got the answer. ”. Descargue el archivo de música MP3 Toitoi san ankou and chiitoitsu riichi mahjong guide a una calidad de audio de 320 kbps. Ryuuiisou. Riichi Book 1. If this pattern is found twice in one hand, an alternative yaku, ryanpeikou, is scored. 737s: 15433 mahjong in 5000m random draws: 0. The player calls out rīchi, which warns the other players of the hand's status as being in. Vector set of riichi mahjong (majiang) elements (number tiles from 1 to 9 in dots, characters, bamboos; winds: east, south, west, north; dragons: white, green, red; dice, pointers: east, south) Mahjong tile on white background . Yeah I think adding riichi is quintessential. The Toronto Riichi Club is excited to announce the first Toronto Riichi Open (TRO). your. Riichi has the most convoluted scoring system of any mainstream mahjong ruleset combined with an above average number of hands that need to be memorized. 2 Han: Sanshoku Doukou: Triple Triplets - Needs three identically numbered triplets across the three suits. LAPOM Championship 2017; World Riichi Championship 2017; Other. Toitoi – Hawke’s Bay Arts & Events Centre opened in February 2020 after completion of the first stage of an earthquake strengthening and refurbishment project. Toitoi with chanta forms honroutou instead. Just like all tile calls, the call itself is optional; thus, an opportunity to call kan is not mandatory. One website in particular really clarified a lot of things about riichi mahjong for me (the in-game tutorial is mostly useless). It is based on the autobiographical novel Kishiwada shōnen gurentai: Chikemuri junjō-hen written by Riichi Nakaba. Since almost a whole suit is removed bad waits become more viable. yaochuuhai. 29. The only wait pinfu gains fu involves the 10 fu gained from winning with a closed ron. Resources. Only a subclass of yakuman, kazoe yakuman, actually counts the number of han. The historic Opera House, built. Yaku - 2 han. You can get all the way to Expert-1 without knowing anything about strategy -- after all, I did. It is possible to fulfill conditions 2 and 3 simultaneously, which awards 2 han. In fact, this yaku may be scored with a noten hand. All at once (Ikkitsukan) 1 to 9 pieces of 1 piece in one kind. To riichi or not to riichi? This is the most common dilemma that most players will face when playing Japanese mahjong. A riichi mahjong library. Dragon tile groups always count for yakuhai. Riichi Chieda (稚枝 利一, Chieda Riichi) is a minor character in AI: THE SOMNIUM FILES - nirvanA Initiative. The project structure is a standard Vue. See all toitoi's items. One pitfall of tenhou and chiihou may be the accidental call for riichi due to the failure of recognition. Ikkitsuukan – <5%. Riichi 「立直」 or 「リーチ」 is the most commonly used yaku in the game. A love with a burning passion: “Coffee and Vanilla”. d3 c5 6. description: This is applied when the player calling riichi wins within 4 tile draws/discards. 74. WRC reference sheet adapted to reflect the terms being used in Final Fantasy's Doman Mahjong. e. Good for Menzen and with good ryanmens but difficult to. Unlike all other possible hands, this yaku emphasizes the discards, rather than the hand itself. "Ready hand" is a rarely used English name for this yaku. If it is a Kan, multiply it by four. Chiniisou 「清一色」 is a standard yaku. 6. No other tile type are used: no simples (2-8) or honors. Japanese mahjong (Japanese: 麻雀, Hepburn: Mājan), also known as riichi mahjong, is a variation of mahjong. Sorry! It's so smelly. / Prepare the lines, the many spears, the fish hooks, the crayfish traps, the round nets, the long nets, eel traps, bobs, the bait and all those things. . 4% Knocked the baby's head. your hand is not a stale lake of fourth place rejectance, yours is a raging torrent of river, an unstoppable flow! yours is a hand of toitoi, a hand of first. Many yaku are pattern-based yaku comparable to "poker hands". This is due to the level of difficulty attaining the hands. toitoi API docs | Scoring demo A Riichi mahjong library in Rust. Lots of men crush on. I’m also fairly confident I can dodge this and I have a whole horde of safe tiles with those 9 bamboos. You pon and kan but T6 East declares riichi, and for some reason you deal the third most dangerous tile right into them for riichi ippatsu pinfu tanyao triple dora, haneman. ) For now, it handles most hand scoring scenarios under standard rules. His early days as a comic artist were developed while he was going to the prestigous Waseda University in Tokyo back in 1990. The Toronto Riichi Club (TORI) is a club based in Toronto, Canada that aims to promote Japanese mahjong in the Toronto area. Crypto East 2-3: Two pairs and a triple, making toitoi a somewhat reasonable ask. The tile layout and graphical hands, as in "physical" hands, are displayed during game play. com to subscribe to the mailing list. Literally, this hand is composed of "all green" painted tiles. Riichi - Ippatsu - Menzenchin tsumohou - Pinfu - Iipeikou. There is a futile pair in your hand. if you do have other tiles to deal, but mistakenly deal the one for the open riichi, you. At least not voluntarily. There are four of each tile, and the tiles are further separated into "suited" and "honors". Business, Economics, and Finance. Toitoi prefer sandy to gravelly streams or lake beds. The biggest problem with open toitoi is that by itself it isn't worth much and it combines very poorly with other yaku. Both involve all four wind tiles. when you've called 4 times, the only one in your hand is 3wan, and the open riichi is 3-6wan), it's yakuman. Mahjong Soul Game Log. Calling kan while in riichi is a risky play though and I personally wouldn't do it unless I'm desperate to add more value to my hand. Chankan is. First, we introduce the average value for all Riichi hands. If the hand contains no honor tiles, then the chinitsu yaku is counted instead. Therefore, you should avoid discarding tiles on which the player declaring riichi can declare ron. this incidentially also solves all fu-related issues I could think of, because the fu a set awards is >= the amount of fu a wait can award (probably). Thanks go to Sjef Strik, Jenn Barr and Benjamin Boas for great help in shedding light on rule. Toitoi vs. Don't try and mawashi against riichi with a hand that's forever away when the dealer is also pushing (S1). No packages published . Very hard. In due time, Mahjong rose in popularity, slowly assimilating Japanese-style innovations. It's a lot of fun but it has a lot of game mechanics (e. 1. Kokushi Musou – 0. If you're in 4th place during the final round, for the love of all that is good, try to put together a hand worth something instead. 2 han (open) Speed. 1. Start Reading. run. if you're one tile away from winning, the game will let you declare riichi. This file contains additional information such as Exif metadata which may have been added by the digital camera, scanner, or software program used to create or digitize it. 6. Blog. ToiToi & Dixi Asia | 1,037 pengikut di LinkedIn. Chiitoitsu requires seven pars, which precludes the triplets for sanshoku doukou. " Toi toi toi " ( English: / ˈtɔɪ ˈtɔɪ ˈtɔɪ /) [1] is an expression used in the performing arts to wish an artist success in an imminent performance. Nagashi mangan 「流し満貫」 is a special yaku. yml configuration for Github Actions. As the name implies, the amount of mangan is exchanged. A Guide to Tenhou’s HTML5 Client; WWYD. Riichi has 8 siblings, four are older and four are younger. The best server to play riichi mahjong online out there isn't originally in English. Mahjong is the ancient asian board game. The platform functions as a gacha game. Haitei raoyue 「海底撈月」 or simply Haitei is a standard yaku, where a player wins with the tsumo on the haiteihai, the last drawable tile from the live wall. Players may very well blindly call riichi without any thought. Kazoe yakuman. Even more if noone else called riichi. ☰ Crate toitoi. For Yakuza, mining open tanyao, yakuhai or even the occasional toitoi will be sufficient. 2. gives a devastating push towards toitoi, with suuankou potential. AnimeSuki Forum > General > General Chat > Sports & Entertainment: Japanese Mahjong ThreadCalvin Adiputra. Reaching is the easiest way to +2000 points (-1K for the reach stick, +3k for. Six years later, Uru disappeared from the. Ikkitsuukan 「一気通貫」, or ittsuu 「一通」 for short, is a yaku, defined as three distinct tile groups containing 123, 456, 789 of one suit. In the main menu, there’s a question mark that will list all of the yakus. If it is closed and a terminal, 2×2×2= 8 fu. However, hands still require at least one yaku in order to score, regardless of the number of dora in the hand. Double riichi: Double-ready - Declare Riichi with your starting hand before any tiles are called. No matter what, you should always get the proper score for counting pons if you follow these steps. /dist: Build output folder. Western Classical Mahjong is the version that was revised from the Chinese classical and was introduced in America. 1 Pinzu versus tonzu. This premise is similar to the chiihou, except the hand wins by discard (ron). This earns 192,000 points OR 288,000 for the dealer. if you riichi and they deal into open riichi, it's 2 hand yaku. The 3 dragon tiles (Red, Green, and White); and the 4 wind tiles (East, South, West, North). Ok, so i've actually been playing 3 different anime mj clients (majsoul, majhime and riichi city) daily for the past month or so. Lather rinse repeat. Welcome to r/Jujutsushi, a subreddit where you can freely talk about all officially-released chapter content for the Shounen Jump series, Jujutsu Kaisen!Please make sure you've reviewed our rules and FAQs!. it's the East round, and with the yaku of riichi, ippatsu, tsumo, haitei. Only a subclass of yakuman, kazoe yakuman, actually counts the number of. chitoitsu on the other hand is an utterly unpredictable tile that u can tanki on anything. Yakuman in this fashion is achieved with the accumulation of 13 han or more via a mixed combination of regular yaku and/or dora. <TAIKYOKU> Start of round - oya Dealer <INIT> Start of hand - seed Six element list: Round number, Number of combo sticks, Number of riichi sticks, First dice minus one, Second dice minus one, Dora indicator. 9%. It contains the 13-tile pattern 1-1-1-2-3-4-5-6-7-8-9-9-9 of the same suit, plus any one more tile from the suit. But a lot of the specific variant's flavour is lost in the process. Yaku - 1 han: Haitei raoyue - Houtei raoyui - Rinshan kaihou - Chankan - Tanyao - Yakuhai. For toitoi (all triplets), you should ideally have some other value within your hand, be it dora, yakuhai, or honitsu. Nakasuji (4, 5, and 6) are the next safest, as they add the possibility of a kanchan. It is a variant of chiitoitsu (seven pairs). within the first six turns) If you call, the hand will be worth at least 5200 points. It is one of the three yakuman gosanke 「役満御三家」, or "the three big families of yakuman". One of the basic combinations suitable for beginners. Dora. No matter what, you should always get the proper score for counting pons if you follow these steps. Yaku - 1 han. Riichi Yokomitsu, Dennis Keene (Translator) 2. Similarly, it's really shitty for defence because you're invariably going to have less tiles to choose from if shit gets too real and you have to abandon your hand. this is handled by prioritizing sets over runs, if necessary. Towa (Toitoi) Set 4 of the same tile and then 2 of the same tile. To make a Riichi declaration after someone else rather than defend. 6%. A tenpai hand with sanankou with toitoi is tenpai for suuankou. It has same rates in gacha as MJS, but gives more pulls weekly(3, can be farmed by logining 6 times and playing 7 ranked games). Riichi Ippatsu Tsumo Dora Aka | Dealer Mangan Tsumo Again going cold, Abraham waits for their opportunity to strike which finally comes around in South 3 taking second row riichi. Japanese mahjong ( Japanese: 麻雀, Hepburn: Mājan), also known as riichi mahjong, is a variation of mahjong. It's recommended in various literature (like Riichi Book 1) that, in general, if you have 5 pairs, go for chiitoitsu. en toitoi. 4) Cut a "useless" tile. Riichi: The player has a fully concealed hand that is one tile away from winning and makes a wager. Be aware that they change mostly every round so. You can also add vibrant colors. It is a variant of chiitoitsu (seven pairs). 「暗順」. bought more games from japan 07 Jan 2022Announcements · 04 Jul 2023. “I've heard from a couple of people this has happened to, mostly people without social media bases, and it isn't too hard to imagine. The variant is one of a few styles where discarded tiles are ordered rather than placed in a disorganized. Yes, but the focus shifts from riichi,tanyao,pinfu to honitsu/(toitoi),honpai in my experience No chii means less open hands, no help in speed improvement. Bd2 d5ToiToi & Dixi Asia | 1,046 followers on LinkedIn. GameStop Moderna Pfizer Johnson & Johnson AstraZeneca Walgreens Best Buy Novavax SpaceX Tesla. Languages. Riichi - Ippatsu - Menzenchin tsumohou - Pinfu - Iipeikou. As you can see, the first choice has the higher EV. If it is closed and a terminal, 2×2×2= 8 fu. This hand stands at 31 han and 50 fu via tsumo: 13 han from shousuushii. Easy. Update: I implemented a proper RNG, optimized the program slightly and let it search through 25 billion random draws:. This hand also includes the regular yaku of toitoi and sanankou as well as two or three yakuhai when applicable. A special pattern of chuuren poutou tenpai produces one with a unique 9-sided wait. 111222333m5557s 7s). LysUltima, Sep 23, 2017 #18. ”. 00031 %, 1 in 326254. フーロ. If the discarded tile is claimed for a chow, pung, or kong the. mahjong japanese-mahjong riichi-mahjong Resources. Upgrading hand values can just occur accidentally, but if you are decisive, any finishing hand is possible. Or? Yes, but the focus shifts from riichi,tanyao,pinfu to honitsu/(toitoi),honpai in my experience Open toitoi suffers from similar problems. Adding to that a San Ankou, a San Kan Tsu, a Riichi, and probably a Toitoi, we're up to 39 Han. Completed Yaku [Chinitsu]. Fukuchi Makoto. They are as follows: At least four pairs in the early stages of the round (i. 5% It seems that I will win a lot. At discretion. A special pattern of chuuren poutou tenpai produces one with a unique 9-sided wait. player: score: Hand scoring. With several middle pairs it is better to go for chiitoitsu because of the difficulty of obtaining pons of the middle tiles. github/workflows: . Probably the single best English reference material for Japanese mahjong, Daina Chiba’s Riichi Book 1 assumes you already have an understanding for basics of the game and dives straight into strategies that will help you better understand how tile efficiency affects your hand, how to play offensively and defensively. Giá trị: 1 han (kín) Khi bài bạn kín và đang Tenpai (nghĩa là, quân trong bài bạn đang chờ một quân cuối cùng nào đó nữa để hoàn thành bài), thì bạn có thể thực hiện yaku Riichi theo các bước: - Nói Riichi và đánh quân tiếp theo của bạn đặt nằm ngang. Riichi Chieda is tall, with brown hair swept back and a brown mustache. Good for Menzen and with good ryanmens but difficult to pon. Exemplos . Love the high-stakes mahjong cash, though. Toi toi toi. I'm not sure you'd be able to find 36. Eventually, Japanese Mahjong, or “Riichi Mahjong”, became the most popular tabletop game in Japan. About this game. Naturally, in English terms, this hand can also be noted as a "straight", similar to the poker hand of the. 3. Tsumo off the dead wall when forming a kong gives 1 han. Ankan. 09-26-2018 Honitsu: NU Club Play: 11 Riichi, ippatsu, tsumo, honitsu, iipeikou, chanta, double ton. This premise is a similar case involving suuankou, which counts as yakuman via tsumo. Japanese Mahjong is a multiplayer game for 4-players, though it can easily be played with two or more players. Those are extremely important fundamental skills and will carry you far. Moving past that logic, I think it's not higher value because you're probably going to be also getting toitoi with lots of dora potential, albeit risky to do so. It also has a very important hand that requires you to have at least a working understanding of that convoluted scoring system, which itself is going to be confusing to beginners who will. In fact, this yaku may be scored with a noten hand. Decent for menzen pinfu, good for tanyao and toitoi. It is defined by a player declaring ron with a starting hand before drawing their first tile and before any called tile. RiichiCity - ACG mahjong games. The issue is that in Riichi Mahjong (the type played in Yakuza/Mahjong Soul/FF14/any japanese game) you can't just make a hand, it needs to be a valid hand (or Yaku). The rules were organized in the Taishō to Shōwa period as the game became popular. On the other side, Half Flush ( honitsu) stands out as the most common yaku that's worth more than one fan, and indeed it is an excellent yaku: it's fairly easy to build and can be used to salvage an open hand. Sinônimos e antônimos de toitoi e tradução de toitoi a 25 línguas. The book is free to download, and written by a pretty strong riichi player. See all toitoi's items. Toitoi live in gently flowing streams and can form land-locked (no journey to sea) lake populations. Hon-/chinitsu are much more common. c4 e6 6. Naturally, in English terms, this hand can also be noted as a "straight", similar to the poker. However in a bizarre turn of of events they face down a Toitoi hadaka tanki and a possible character Honitsu. [citation needed]The scoring system uses structural criteria as well as bonuses. KOIZUMI, Riichi March 21, 1919 - November 20, 2014 It is with very saddened hearts that we announce the passing of Riichi Koizumi. While regular yaku may be stacked in one hand to raise value, the same can be done with different yakuman, where applicable. Many old mahjong tiles on wooden table. He wears a white blazer with two rows of white buttons, a light red shirt inside, and a light red bow tie on the chest; plus, he wears a pair of white trousers and a pair of white. 0%. This call forms a tile grouping of four identical tiles, called kantsu「槓子」. Either way, yakuman is likely guaranteed with the winning tile. Auto rotate discard tiles. 5) Repeat. There are several different kinds of hands, and some are worth more than others. There is a futile pair in your hand (other 2 have been discarded). Know when to call for keiten to avoid noten penalties, especially. So, players making the last discard of the. Beside, our service trucks are equipped with state-of-the-art. , the other two of that tile pair have been discarded) There is no pair of value tiles in your hand. Yaku 「役」 are specific hand patterns or conditions needed in order to score a hand. toitoi > iipeikou (i. Both of the other groups must be shuntsu of different suits. This hand consists of seven pairs, where no two pairs may be identical. Example: 2 han 110 fu. On one hand, winning with a riichi hand gives you at least one extra Han. 78m checks/s 1557s: 31080 mahjong in 10140m random draws: 0. x. Rinshan 2. This is because speed makes up for “score” and “defence. 2 Han: Sankantsu: Three Quads - Requires three quads, which are considered as triplets plus one extra. Three combinations actually form yakuman: Toitoi + Junchan = Chinroutou. Upgrades for riichi win argue for riichi, but my uncanny ability to fail at drawing tsumo for the win or ura dora may completely counterbalance that edge. 2 Han: Sankantsu: Three Quads - Requires three quads, which are considered as triplets plus one extra. 1 Table notes. Players must finish hands before others do; and each yaku. Here’s the list of basic game terms in Japanese, with kanji given whenever possible. This makes it really hard to get a high scoring hand with toitoi unless you are really lucky. This hand may be open or closed. They can be seen in the open but often seek cover. Dora 「ドラ」 is a feature to the game, where possession of specific tiles instantly grants the hand 1 han per tile. 6%. It is essential to know the yaku for game strategy, since a player must have a minimum of one yaku in their hand in order to legally win a hand. Nf3 Nf6 4. Towa (Toitoi) Set 4 of the same tile and then 2 of the same tile. Riichi Nomi member here. Create artwork with different tools, such as pencils, brushes and stamps. Riichi mahjong is definitely the most popular variant among the money demo in NA/EU (men aged 18-40), and this subreddit will naturally be likely to support the style reflective of its membership. It's also fairly. Some combinations form a different yaku which implies one component of the combination, and as a result can never be counted: Toitoi + Chanta = Toitoi + Honroutou. Riichi (hand is fully concealed and player makes Riichi bet, see below) Menzen Tsumo (hand is closed and win is by self-draw) Toitoi (hand is all triplets plus a pair). Of all the standard yaku, sankantsu is the most difficult and least frequent. Generally, this applies to aiding the formation of certain yakuman hands, however, there also exists a variation that applies to. •. The difficulty stems from the need to call kan three times; but. The bet is to complete a hand without altering it from this point on. Modules [−] Crate toitoi. For this yaku, every tile group and the pair must contain at least one terminal. Also, I should say, those steps are not mutually exclusive. While the basic rules to the game are retained, the variation features a unique set of rules such as riichi and the use of dora. Daichiishin. Putting off the riichi until the eleventh go-round was an interesting decision (and questionable given the situation; a riichi this late only reduces the chances of winning what is a. Menzen tsumo with toitoi is actually the yakuman, suuankou. You should aim for a closed hand or at least wait for the shape to improve and then maybe call. If you want tiles that are 36mm, you'll need to get a chinese set. StuffedDuck likes this. Edit: <-much better picture; must worship moe and tony at the same time Note: this is NOT a real religion, no matter how much I claim it to be. Mahjong Soul is the better established client with a bigger player base, queue times never an issue with connections never too much of an issue. tile: Provides a tile type and associated functions. Toi toi toi. Only the triplets need to be concealed, the rest of the hand can be open. Whakatikatikangia ngā aho, ngā pīhuka maha, ngā matau, ngā tāruke, ngā pouraka, ngā kupenga, ngā hīnaki, ngā toitoi, ngā mōunu me ērā katoa (WT 2013:25). By Muller On 8 November 2017 In Strategy You may have heard of the toitoi dash – it’s the hot new meta, popularized by zeRo and his new book 0秒思考の麻雀 ( Zero-byou Shikou. In this situation, I’d try to go for an all simples by dropping the 1 char. Or you could just go for toitoi and. tenhou. Marvin's Art Studio. Trong biến thể này, nhiều phần luật chơi được thay đổi so với nguyên gốc, với sự xuất hiện của riichi và. move ever forwards. Considering that the lowest hand value in riichi is 1,000 points (1,500 dealer), there is a 192:1 spread. Complete the shapes with the same type of tiles. You can play for free. Packages 0. Clearly, basic yaku occur far more frequently than complex ones. If you kan after you declared riichi you'll still be in tenpai and your hand is obviously still considered closed. It also cannot be combined with chiitoitsu, since it doesn't use mentsu .