What is Chiihou?
Chiihou (Earth Hand) is a yakuman where a non-dealer (South, West, or North seat) wins on their very first draw. Your starting 13 tiles must be tenpai, and your first drawn tile completes the hand.
With an occurrence rate of about 0.0005%, it’s extremely rare - you might see it once in a lifetime. Like tenhou, it’s determined purely by luck.
Requirements
| Condition | Details | Notes |
|---|---|---|
| Non-dealer | South, West, or North | Not dealer |
| First draw | Win on first tile drawn | Starting hand in tenpai |
| No calls | No one has called | No pon, chi, kan |
| First turn | Before your first discard | Strict timing |
What Invalidates Chiihou
| Situation | Reason | Result |
|---|---|---|
| Someone calls pon/chi | First turn disrupted | Normal tsumo |
| Someone kans | First turn disrupted | Normal tsumo |
| You’re dealer | Dealer = tenhou only | Must win on deal |
Chiihou Forms
Pinfu-Type Chiihou
Starting: 123456789m EEE
First draw: 7m
Result: Pinfu + Sanshoku + ChiihouDouble Yakuman Chiihou
Starting: EEE SSS WWW NNN H
First draw: H (haku)
Result: Shousuushii + Chiihou (Double)Chiitoitsu Chiihou
Starting: 11m 33p 55s EE SS WW N
First draw: N
Result: Chiitoitsu + ChiihouChiihou vs Tenhou
| Aspect | Chiihou | Tenhou |
|---|---|---|
| Who | Non-dealer | Dealer only |
| When | First draw | On deal (14th tile) |
| Probability | ~0.0005% | ~0.0003% |
| Frequency | ~1.7x more likely | Rarer |
Probability
Statistical Analysis
| Item | Value | Notes |
|---|---|---|
| Tenpai rate | ~10% | With 13 tiles |
| Winning tile | 1/34 | From remaining |
| Chiihou rate | ~0.0005% | Combined |
If You’re Tenpai on Deal
Mental Preparation
-
Don’t expect too much
- Probability is very low
- Normal win is fine
-
Hope no calls
- Someone might call
- Leave it to fate
-
Draw confidently
- Don’t be nervous
- Stay natural
When Achieved
1. Check drawn tile
2. Declare "Tsumo, Chiihou"
3. Reveal hand
4. Confirm points (48,000)Chiihou Psychology
The Undefendable Yakuman
-
Pure luck
- Starting hand and draw
- No skill involved
-
Cannot defend
- Opponents can’t do anything
- First draw can’t be stopped
-
Call to disrupt?
- Theoretically possible
- Not realistic
Local Rules
Chiihou Variations
| Rule | Treatment | Notes |
|---|---|---|
| Standard | Yakuman | Normal rule |
| Some areas | Double yakuman | Rarity valued |
| Rare cases | Not recognized | Uncommon |
Call Handling
- Ankan also invalidates (usually)
- First turn definition varies
- Strict application
Common Mistakes
-
Dealer confusion
- Dealer cannot get chiihou
- Dealer only has tenhou
-
Call impact
- Even one call cancels it
- Easy to miss
-
Second draw+
- Only first draw counts
- Turn 2 onward = invalid
-
Ron confusion
- Chiihou is tsumo only
- Ron = renhou (local rule)
Related Terms
- Tenhou: Dealer wins on deal
- Renhou: First turn ron (local)
- Tenpai: One away from winning
- Yakuman: Highest scoring hands
Summary
Chiihou (Earth Hand) is a yakuman where a non-dealer wins on their very first draw. With about 0.0005% occurrence, it’s extremely rare but offers every player an equal chance at glory. If you find yourself tenpai on your starting hand, believe in your luck and draw that first tile. Chiihou is mahjong’s goddess smiling upon you - a wonderful gift of pure fortune.