Riichi Mahjong Strategy.pdf

Basic lone tiles

Honor tiles:

Helpful tile count: 3

Terminals (1,9):

Helpful tile count: 11

2,8:

3-7:

Helpful tile count: 15

Helpful tile count: 19

3-7 tiles >2,8 tiles >1,9 tiles > Honor tiles Example 1: Sample starting hand East round, seat-west Dora: North wind

Example 2: Sets and lone tiles

Example 3: Poor hand exception Seat:west

Basic set waits Pair to triplet (2 tiles)

Edge wait/Penchan (4 tiles)

Middle wait/Kanchan (4 tiles)

Double middle wait/Ryankan (8 tiles)

2-sided/Ryanmen (8 tiles)

3-sided wait (11 tiles)

(Requires 3 tiles) Example hand: Choosing the best wait

Example hand: Improvable waits

Less useful tiles and overlapping waits 1) less useful tiles

2) Overlapping waits

Example hands

Basic pairs, part 1: No clear pair hands Pair waits Single pair wait

Double pair waits

More complex pair waits

Example hands

With no clear pair, choose set waits over good pair waits

Basic pairs, part 2 In general, keep 2 pairs …

Lost tiles:

And only 2 pairs:

Review of the basics Middle lone are better than edge lone tiles Sometimes, lone tiles can be less useful (or more useful) than normal Groups of 2 are better than lone tiles Some groups of 2 are better than other groups of 2 Be careful about breaking up completed sets of 3

Focus on making hands rather than making yaku Think about lost tiles There are plenty of exceptions!

Check the dealer, dora, and score Dora: West wind

Dora: 8m

Dora: 9s

Dora: 8p

Dora: 2p

Dora: West wind

Basic defense Genbutsu – tiles the player has discarded and all tiles discarded after riichi.

Suji

Suji comparison Terminal waits:

2/8 waits:

3/7 waits:

Non yakuhai honor tiles, yakuhai honor tiles, terminals When playing aggressive against a riichi, discard safest useless tiles first

When to defend: Often against riichis (Maybe no when: in tenpai, close to a big hand, or in a must win situation) Against big open hands Against the dealer In higher level rooms, consider defendig against damaten hands as round progresses

Lost tile and furiten

Flexible hands Dora: 5s

Complex hands

More defense Walls:

eliminates

and

making

safer

makes

safer

Red 5 discard:

safer

Outer tiles:

Discarded early makes tiles closer to the edge likely safe

Hand range:

Value considerations: Suji guarantees no pinfu Honors and terminals guarantee no tanyao Playing in on a dora guarantees at lest that dora Near dora tiles are at risk for playing into a hand with dora Special yaku considerations: Honitsu/ Chinitsu, Chanta/ Junchan

Situational play and declaring riichi

When to consider not riichi`ing: Closed 4 han (or 6 han) hands

No riichi ron: 7700, Riichi ron: 8000 (12000) No riichi tsumo: 8000, Riichi tsumo: 12000 (rare 16000) Very improbable hands

Winning is more important tan points Last draws, unlikely to win Riichi can be better with tricky waits Player’s choice: 2/3 han (pinfu) hands

No riichi ron: 3900, Riichi ron: 7700 (8000/very rare12000) No riichi tsumo: 5200, Riichi tsumo: 8000 (12000)

No riichi ron: 2000, Riichi ron: 3900 (7700) No riichi tsumo: 2700, Riichi tsumo: 5200 (8000) South 4: You (South) – 23500 West- 24000 North -14000 East – 33500 South 4: You (West) – 40000 North - 27000 East - 23000 South - 10000 South 3: You (East) – 8000 South - 45000 West -26000 North – 21000

South 3: You (South) – 8000 West- 45000 North -26000 East – 21000 South 4: You (West) – 8000 North - 45000 East -26000 South – 21000 East 1, renchan 2, 3 riichi sticks in middle: You (West) – 24000 North - 25000 East -22000 South – 26000 South 2: You (East) – 55000 South - 21000 West -13000 North – 11000 South 4: You (North) – 29000 East - 26000 South -23000 West – 22000 West 2,8th turn You (North) – 24700 East - 24400 South -28100 West – 22800

Dora: 9m South 4, renchan 4,3 riichi sticks in middle: You (South) – 23500 West- 23000 North -22800 East – 27700

Thenhou and last place avoidance: East – South matches Ippan (general) room points gain: 1st = +45 Joukyuu (expert) room points gain: 1st = +60, 2nd = +15 Tokujou room points gain: 1st = +75, 2st = +30 Houou room points gain: 1st = +90, 2st = +45 4th dan point loss: 4th =-90 6th dan point loss: 4th =-120

3 kyuu point loss: 0 1 kyuu point loss:4th =-30 (can’t rank down) 2st dan point loss: 4th =-60 A note on tiles near triplets and pairs

Awareness Recognizing empty waits or weak waits No 1 bamboos remaining

Noticing curious discards and important (dora) discards Seeing waits (for defense and tile distribution) Noticing discards from the hand vs tiles discarded after being draw Hand planning and defense planning

Defense! Want to avoid: Unnecessary risks (genbutsu before honor tiles or suji) Excessive risks High risk low reward Defend against riichi Defend in dangerous situations (Dealer with double east and dora/yakuhai) Avoid dangerous discards late Try to be aware of all genbutsu, all suji, and all walls Easy to miss: Middle suji (ex 5 when 2 and 8 are safe) Walled tiles late Be wary of honor tiles when they are missing late There are many easily believable “fake rules” -A player discarding a lot of one suit doesn’t make every tile in that suit more likely to be safe (depends on what the tiles are and if the tiles came from the hand…) -A player not discarding any of one suit doesn’t always make that suit the most dangerous (depends on held tiles, most recent discards from hand…) Safe vs dangerous first Play dangerous tiles while you think they are safe Play safe tiles first when you think (or know) a player is in tenpai

In some cases, the normally safer tile may be more dangerous When defending , may want to play tiles that are safe but more dangerous to others, and hold tiles that are safe to everyone (can think of it as the “dangerous first” rule for other players) Defensive hand progression and exceptions to the efficiency rules Defensive hands

Can give chance at more value. Particularly when dora is a terminal or honor tile Defensive vs risk chiitoitsu

Defensive vs risk open yakuhai hands

Hold a lone 3 over a lone 6, and a lone 7 over a lone 4

Defensive progression

Hand reading and dangerous tiles, general topics You can’t know the opponent’s wait for sure

However , the tiles that complete the wait you knew about are clearly more dangerous Hand reading basics The question: Why would you discard that tile, or why would you hold that tile? Two big notes: unusual held tiles and early stronger number tile discard Early 1 (terminal) before non yakuhai: Higher likelihood of needing 2,3,5 Early 2(non terminal) before a 1 or non yakuhai: Higher likelihood of needing 3, 6 Early 3 , 4, 6, 7: Higher likelihood of needing next suji towards the middle Early 5: Higher likelihood of needing 1, 4, and/or 6,9

But , not all early discard indicate a wait:

This is less applicable when a group of 2 is discarded Riichi/near riichi discards from hand: Nearby tiles may be dangerous

Before discarding suji near riichi tile, think if it completes a wait that makes sense 5799p->799p->79p 799p, 899p, 779p, 889p, 999p 6899p->899p->99p 899p->888p 889p is unlikely against a strong player (barring special hands, defensive play, or 9p dora) But , not all riichi discards even indicate a wait

It is rare to see a riichi on an improved wait: 46->67

So, the tile 4 away from the riichi tiles is not more dangerous. But it may be a separate wait: 24467->234 67 Or, may be a 3 sided wait: 344567p->34567p Open hands are much easier to read like this. Tiles close to the most recent discard from the player`s hand are quite often dangerous The “center half suji” If a player discarded 1, 2, or 3 (or 7, 8 or 9) early, the middle tile on the same suji is slightly safer than the opposite edge on the same suji 1-4-7 2-5-8

But, this doesn’t mean it’s safer compared to other tiles! Hand reading and dangerous tiles, specific examples Must use good reasoning and understanding to put together information accurately 1.

You can see all

Player riichis and discards

from hand

Is safer or more dangerous? (Walled 3 makes 2 safer, riichi on 5 makes 2 more dangerous)

2.

Player discards early

You can see all

Is safer or more dangerous? (Early 7 discards makes 3/6 more dangerous but you can see all 6) 3.

Player discards early

Player riichi and discards

from hand

Is safer or more dangerous? (Early 7 discards makes 9 safer as it’s outside of the 7, but tiles near riichi discard more dangerous)

4. Player discards early

Player riichis and discards

Is or safer? (Early 2 makes 5 safer than 8… usually)

5.

Player discards early

Player riichis and discards

Is or safer? (Early 2 makes 5 safer than 8… usually)

maybe unlikely 6.

Player discards early

and discards

on the draw

You can see all

Is safe or more dangerous? (Early 6 makes 2/5 more dangerous. 6 then 8 may change meaning but 8 was in the draw . Does walled a matter?)

A Trick with middle tiles, suji, and walls: For 4, 5, 6 to be safer, usually you need to see the suji on both ends With walls, you sometimes only need to see one suji All 2 out: safe 7 makes 4 likely safe All 3 out: safe 7 makes 4 likely safe (same as a suji terminal) safe 8 makes 5 likely safe Strong drawing ranges

Don’t do this incorrectly!

Intimidation plays and aggressive plays

+1300 (2000) on ron, +3000 if only player tenpai Kan double east or double south Other (closed) kans Dora pon Obvious honitsu or chanta Giving up on tenpai too easily might be giving up too much of an edge: -Can stick to your hand when other players’ hand are probably cheap -Sometimes knowing likely safe tiles helps you play safe and hold on to your hand

Special tips and tricks Predicting tiles in the wall Early 1 may mean player has 4 (especially 1/9 before non yakuhai honor tile) Early 2 mean player likely doesn’t have 3 If tile behind a wait aren’t discarded, maybe no one has them (67789 with two 7’s discarded) 5 over 6 Hands that discard 6: 246, draw 3

46, draw 3 Hands that discard 5: 135, draw 2 579, draw 8 35, draw 2 57, draw 8

There is surely much more out there… Example hands from actual matches South 1, west wind hold http://tenhou.net/0/?log=2014102909gm-0089-0000-xd06647d172ad&tw=1 South 2. safe as dealer with 4 dora http://tenhou.net/0/?log=2014111113gm-0029-0000-x60e12725fea3&tw=1 East 2, reckless read as dealer http://tenhou.net/0/?log=2015051114gm-0029-0000-72adbbb6&tw=1 South 1. steal the win from the open hand http://tenhou.net/0/?log=2015060408gm-0029-0000-081d21a3&tw=3 East 3 (1), riichi tile suji; South 2 (1), north wind hold http://tenhou.net/0/?log=2015061112gm-0029-0000-226c14a4&tw=3 South 1, missed dodge . http://tenhou.net/0/?log=2015062114gm-0029-0000-d74a7770&tw=0 East 2. tenpai vs 2 riichis: South 4, riichi and dealer damaten http://tenhou.net/0/?log=2015072806gm-0029-0000-5df39d9d&tw=0 East 1 (1), after a frustrating loss http://tenhou.net/0/?log=2015080313gm-0029-0000-caab9475&tw=1 East 2 (1). 9 vs suji 3 http://tenhou.net/0/?log=2015080808gm-0029-0000-9ae46da2&tw=0 South 1 (1). north wind hold http://tenhou.net/0/?log=2015072407gm-0029-0000-bf6c2763&tw=3 South 3, situational risk http://tenhou.net/0/?log=2015080613gm-0029-0000-6e3574b7&tw=2 South 2. houou room, dodge the open hancj http://tenhou.net/0/?log=2015090213gm-00a9-0000-baee5e89&tw=0