[Mahjong Improvement Roadmap #3] Build Your Offensive Fundamentals

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[Mahjong Improvement Roadmap #3] Build Your Offensive Fundamentals

[Mahjong Improvement Roadmap #3] Build Your Offensive Fundamentals

In STEP 2 you learned tile efficiency. Now let’s learn to convert speed into wins with solid offensive decisions. What follows is a foundational way to think; as you grow stronger, you’ll layer in advanced ideas (fine-grained push/fold, score-optimized riichi decisions, table control).

Series: STEP 1 → STEP 2 → STEP 3 (this page) → STEP 4 → STEP 5

1. Introduction

Offense is not “always push.” It means choosing lines that win the hand when the situation favors you. The basics here will help you act decisively, and later you’ll refine them with advanced, situational theory.

2. What Is “Offense” in Mahjong?

The aim of offense is to win faster and for higher value. Speed matters because only one player wins each hand—if you win first, you both secure your points and deny others from winning (which also trims your potential losses in the round).

Riichi Power

Declaring riichi locks your hand, but gives it explosive scoring potential—base han from “Riichi” plus chances for ipatsu, ura dora, and tsumo. This can make your hand’s value scale up dramatically (often described as “doubling up” with added han).

  • Ura dora adds expected value; even on average, it meaningfully increases your hand’s score.
  • Riichi also applies table pressure, shrinking opponents’ freedom and knocking some out of their attacks.

Using Calls for Speed

Calling (chi/pon/kan) is another way to attack by prioritizing speed. It often trades away hidden value from riichi, but can seize the initiative before others. When calling still keeps your hand high-value (e.g., honitsu/chanta/yakuhai combinations), it becomes a powerful offensive tool.

3. Core Decision Points

Riichi Decisions

Declare riichi when one or more of the following align:

  • Your wait is wide (e.g., ryanmen/two-sided).
  • Your hand already has enough value (riichi will push it higher or secure the win).
  • Opponents are not pressing yet, so the field is safe enough to fight.

Hold riichi when any of these apply:

  • Your wait is poor (single, edge)—bad equity versus the field.
  • Score situation means even a cheap win is enough (e.g., last hand where any win secures 1st).
  • Your hand is already high-value without riichi (e.g., guaranteed mangan or better).
If two or more of the “go-riichi” conditions fit, go ahead and declare riichi first. If only one fits—or a “hold-riichi” condition also applies—reconsider whether riichi is truly best.

Using Calls (Chi/Pon/Kan)

Pros: gains speed; when the structure stays high-value even with calls (e.g., honitsu, chanta, yakuhai mixes), it remains a strong attack.

Cons: you lose riichi; reveal information to others; and you usually hold fewer safe tiles, which raises your risk of dealing in if the table heats up.

Call when you can stay high-value while accelerating, or when speed is mandatory for the score situation. Avoid calling when you need to hide information, aim for higher value, or you specifically want to keep safe tiles to avoid dealing in.

Balancing Speed and Value

  • Leading (top): prioritize speed; small wins lock your position.
  • Trailing (last): prioritize value; you need bigger hands to catch up.
  • When someone else looks fast: even if it lowers value, prioritize speed to seize initiative and reduce deal-in risks.

4. Worked Examples (Riichi)

Example A (Riichi)

Hand: [2・3・4] "6・7・8" [白・白・白] (5・6) (9・9)
Status: No opponent has declared riichi yet.
→ Wait is two-sided (good) ✓
→ Opponents are not pressing; table is safe enough ✓
→ With ura dora, hand can reach 5200 (non-dealer) / 7700 (dealer) ✓
Riichi recommended.

Example B (Consider Holding)

Hand: [1・2・3] (4・5・6) [中・中・中] "8・9" (9・9)
Status: An opponent has already declared riichi.
→ Wait is edge (poor) ✗
→ Opponent riichi in field; not safe ✗
→ With ura dora, value can reach 5200 (non-dealer) / 7700 (dealer) ✓
Riichi should be considered carefully.

Example C (No Need to Riichi)

Hand: [1・2・3] [4・5・6] [7・8・9] [東・東] [發・發]
Status: No opponent has declared riichi yet.
→ Wait is shanpon (pair wait) (poor) ✗
→ Opponents are not pressing; safe enough ✓
→ Honitsu + yakuhai makes the hand already mangan without riichi ✓
Two good conditions are present, so riichi could be fine, but the hand is already high-value. Declaring riichi might scare discards away. No need to force riichi.

5. Practice Methods

  • Before declaring riichi, compute the winning score you’re aiming at. As a simple rule of thumb: if, even without ura dora, you can reasonably expect 3900 or more as non-dealer, riichi is often worthwhile.
  • Review replays and ask: “What if I had riichi’d / avoided riichi here?” to compare outcomes.

7. What Comes Next

With offensive fundamentals in place, we’ll tackle Defense (STEP 4): when to pull back, how to identify safe tiles, and how to minimize deal-in risk while keeping win paths open.

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