Yaku compatibility: Difference between revisions

This is a table showing the compatibilities of the different [[yaku]] with each other. While yaku may be combined in one hand, some yaku simply cannot combine with each other due to tile counts and patterns. In other cases, one yaku would always imply another. For instance, a [[junchan]] hand has a terminal or honor in every group. So it would qualify for [[chanta]] for having a terminal in every group. By rule, two yaku cannot be combined if one always implies the other. There is a partial exception to this as [[shousangen]] always implies at least two [[yakuhai]] for sets of dragons, but they are not necessarily the same two yakuhai so they are counted in addition.

Yaku strategy involves viability to form yaku and maximizing hand value, if possible. This maximization often involves the recognition of the different yaku forming in one hand.  Often, this affects the decision which tiles to keep and which to discard.

Whether or not these combinations are actually combinations depends on the technical definition of the yaku. Some yaku are restricted versions of other yaku, such as junchan and chanta. There are two alternative ways to define this in the rules: either chanta can require that the hand contain at least one honour tile, or it can allow no honour terminals, but with a separate rule saying that chanta and junchan cannot both be counted. In this case, since junchan is higher-scoring, any chanta hand without honours, while qualifying for chanta, would never score it. Most of these combinations, with the exception of toitoi + mentsumo, are based on the assumption that the yaku are defined using the second method.