What is Anzen-hai?
Anzen-hai (Safe Tiles) are tiles that have a low probability of dealing into an opponent’s hand. When someone declares riichi or appears to be in tenpai, choosing safe tiles helps avoid costly deal-ins.
There are completely safe tiles (100% safe) and relatively safe tiles (semi-safe), which require different strategies depending on the situation.
Safety Levels
| Type | Safety | Description |
|---|---|---|
| Genbutsu | 100% | Same tile opponent discarded |
| Same-turn safe | 100% | Tiles discarded same turn as riichi |
| Early honors | 90% | Honor tiles cut early in game |
| Suji | 70% | Tiles that deny ryanmen waits |
| Kabe | 60% | Safe due to 4 tiles visible |
| One-chance | 50% | 3 tiles visible, edge safer |
100% Safe Tiles (Genbutsu)
Genbutsu principle:
- Tiles opponent already discarded = 100% safe
- Guaranteed by furiten rule
- Most reliable safe tiles
Same-turn safety:
- All tiles discarded in riichi turn = safe
- Becomes dangerous from next turnIdentifying Safe Tiles
| Situation | Safe Reason | Caution |
|---|---|---|
| Early honor discard | Likely not yakuhai | Yakuhai are dangerous |
| Terminal suji | Denies ryanmen | Watch kanchan |
| 4 tiles visible | Can’t physically wait | Kokushi exception |
| Near dora | Often cut early | Can be reverse |
Safety Priority Order
1. Genbutsu (100% safe)
2. Early-cut non-yakuhai honors
3. Terminal tiles with suji
4. Kabe tiles (4 visible)
5. One-chance tiles
6. Near-dora tilesSuji Theory Basics
Suji relationships:
1-4-7 suji
2-5-8 suji
3-6-9 suji
Application:
4 passed → 1 and 7 are suji
5 passed → 2 and 8 are suji
6 passed → 3 and 9 are sujiKabe Theory
| Visible Tiles | Safe Tiles | Reason |
|---|---|---|
| 4× 3-tile | 1-2 | 23 wait impossible |
| 4× 7-tile | 8-9 | 78 wait impossible |
| 4× 5-tile | 3-4, 6-7 | Ryanmen impossible |
| 4× honor | All others dangerous | Kokushi possibility |
Situational Safety
| Situation | Priority | Reason |
|---|---|---|
| Just after riichi | Genbutsu first | Certainty matters |
| Late game | Genbutsu over suji | More irregular waits |
| Dama tenpai | Honors, terminals | Infer from hand type |
| Multiple riichi | Shared safe tiles | Must be safe for all |
When No Safe Tiles
1. Choose highest safety
2. Use suji on terminals
3. Pick the lesser evil
4. Accept lowest damageAdvanced Safe Tile Reading
From Discard Patterns
| Discard Pattern | Likely Wait | Dangerous |
|---|---|---|
| All middle tiles | Tanyao type | Terminals safer |
| Flush-looking | Flush hand | Other suits safe |
| Scattered | Yakuhai/toitoi | Honors dangerous |
| Many terminals | Middle tile wait | 4-5-6 dangerous |
Reading Opponent’s Hand
Fast riichi → Good shape (suji effective)
Slow riichi → Irregular wait (genbutsu priority)
Has calls → Visible yaku
Closed → Harder to read but suji worksCommon Mistakes
-
Genbutsu confusion
- Other player’s genbutsu is dangerous
- Only THAT player’s discards are safe
-
Suji overconfidence
- Doesn’t work for kanchan/penchan
- Shanpon also bypasses suji
-
Honor tile safety
- Only early-cut ones are safe
- Mid-late honors are dangerous
-
Kokushi blindspot
- Terminal/honor tiles watch out
- Even edge tiles are dangerous
Wait Type Statistics
| Wait Type | Frequency | Suji Effectiveness |
|---|---|---|
| Ryanmen | ~60% | Very effective |
| Kanchan | ~15% | Ineffective |
| Penchan | ~10% | Partial |
| Shanpon | ~10% | Ineffective |
| Other | ~5% | Case by case |
Related Terms
- Genbutsu: Opponent’s discards
- Suji: Ryanmen-denial theory
- Kabe: Wall (4 tiles visible)
- Betaori: Full defense
- Furikomi: Dealing into opponent
Summary
Anzen-hai (safe tiles) are crucial for avoiding deal-ins. Genbutsu (opponent’s discards) are 100% safe, while suji and kabe provide relative safety. Master the principle “their discards = safe for them” first, then learn suji theory. Correct safe tile selection reduces deal-ins and steadily improves your results. Balance offense and defense using safe tiles wisely.