Elements of mahjong gameplay can be categorized as either Offensive or Defensive play. Offensive play is concerned about hand development and attaining tenpai before anyone else. Defensive play relies on discarding safe tiles in order to avoid losing by ron.
Essentially, the game of Japanese mahjong is a 4-way race towards tenpai and ultimately winning the hand to accumulate points. The offensive and attacking mindset has tenpai as the goal.
Open vs Closed hands
Aside from tenpai vs not in tenpai, a mahjong hand may be characterized in these two states: Open and Closed. It is important to know when to determine the time to open the hand and when to remain closed. This decision may be affected by the hand's composition, which looks for any yaku.
Therefore, familiarity with the list of yaku greatly aids with this thought process. Other factors may include: the state of the other players, how many tiles are remaining in the live wall, and/or the need to go on the offensive or remain defensive. Combined with a particular yaku, opening the hand increases the speed of development leading to tenpai. If this is the player's current goal, then opening may be advantageous.
Typically, an opened hand results in a decrease in value. Many of the yaku listed decrease by a yaku of 1. For some yaku, the state of open vs closed is irrelevant. More often than not, the "1-yaku minimum" requirement applies here.
While Japanese mahjong is often a race to be the first to tenpai and win, it is also important not to lose points. Especially when an opponent has declared riichi, the game becomes a form of "minesweeper", where the objective changes from winning a hand to not playing into an opponent's hand.
In this case, it is important to note the discard pile. Due to furiten, the discard pile is a key indicator of safe tiles. For one specific player, the tiles in the discard pile are automatically 100%. However, that may not be the case involving the other two players.
In general, it is better to lose points via an opponent tsumo than ron. This is due to the point-swing of a player vs an opponent. A player winning via tsumo or ron receives the same or a similar amount of points either way. Via tsumo, the point loss is not as severe as ron, because the point loss of tsumo is shared among the other players. In contrast, ron is a complete point loss from one player paying the whole amount.
Bailing is the practice of abandoning the idea of winning the hand. Instead, the aim primarily focuses on pure defensive play. In turn, a player seeks the best tile to discard to avoid playing into ron. This is best achieved by figuring out the safe tiles. This strategy is employed, when a player believes:
- The hand is no longer worth pursuing
- The likelihood of winning the hand is low
- The opponent(s) threaten with a potentially high value hand
Sometimes, some degree of unconventional play is used. This is geared towards the "unexpected". Many strategies in the game often falls under "conventional wisdom". However, sometimes, players may "think outside the box" in order to fool and trick other players. Often, these kinds of plays throw off other players psychologically.