In order to be able to build the best hands, you need to know both how to plan out your play with a hand, and how to execute that plan. This is the essence of hand development: taking that group of 13 useless tiles you start with, and using them to build a tenpai that wins you the game. In riichi, you are constantly confronted with choices like “Do I open my hand?”, “Do I just try to get to tenpai quickly, or am I okay with a slower, more valuable hand?”, and the ever-important “Do I fold?” The yaku are basically your toolbox of techniques to build hands, so understanding each of them is critical (especially in games where they contribute more to scoring, like when playing without open tanyao or red fives).
This is the first article in Yaku, Hai!, a new series of articles which go into detail on each of the yaku in turn, explaining the rules surrounding them, when you would use them, and the nuances which may not be apparent at first glance. This first article covers the single most important yaku: the titular riichi. We’ll also cover riichi’s brother double riichi and cousin ippatsu, since their the strategy is simply a part of riichi’s.
Riichi is simple on the surface: stay closed, get tenpai, declare riichi, profit! But both the rules and strategies are very complex, making it one of the most difficult yaku to master. Riichi is one of the best reasons to stay closed until you hit tenpai, but that’s not all. There is an incredible amount of strategy that goes into the decision of when to riichi or not, and there is far, far more than one article’s worth to say about it.