American Mahjong Rules

A set is 152 tiles: three suits of 36 (Dots, Bams, Craks, numbered 1 to 9, four of each number), 16 Winds (four each of North, East, West, South), 12 Dragons (four Red, four Green, four Soap), 8 Flowers and 8 Jokers.

There are exactly four naturals of every number, wind and dragon, and eight Flowers. This arithmetic is what makes a quint need a Joker (see S-5) and what lets a player count a tile out: three showing means only one is left anywhere.

All eight Flowers are interchangeable. Numbers, seasons or pictures on individual Flower tiles have no meaning on the card. Flowers belong to no suit.

The Dragons pair with the suits: Red with Crak, Green with Bam, Soap (White Dragon) with Dot. This pairing holds on every American card.

Soap (White Dragon) is the only tile that can stand for a zero. It is always the White Dragon and it is also the zero; both are true. When a hand uses it as a zero it has no suit and may sit with any suit. Soap-as-zero may never be used inside a consecutive run. A Soap printed as the zero of a year or number group is serving as the zero in that group and takes no suit from the group.

Jokers are wild tiles with restrictions, stated in section 9. A set without Jokers is completed with Joker stickers on spare tiles; the League's card assumes eight.

Blank tiles are not part of the game. Playing with blanks is a house variant (section 17).

A hand is 14 tiles arranged exactly as one line on the current card. Thirteen tiles are held during play; the fourteenth completes the hand.

Matching tiles are identical tiles: same suit and number, same Dragon, same Wind, or any Flowers. Two identical tiles are a pair; three are a pung; four a kong; five a quint; six a sextet.

Every other grouping on the card, including NEWS, a year such as 2026, and any run of different numbers, is made of singles and pairs. It is not a set of like tiles, so it cannot be called from a discard, exposed, or filled with a Joker.

There is no chow in American Mahjong. A discard is never claimed to complete a run.

A quint must include at least one Joker and a sextet at least two, because only four naturals of a tile exist. The one exception is Flowers: eight exist, so a quint or sextet of Flowers can be all natural.

A pung, kong, quint or sextet may be made entirely of Jokers. No minimum number of naturals is required.

A hand made only of singles and pairs cannot take a Joker anywhere and is jokerless by structure.

The National Mah Jongg League publishes a new Official Standard Hands and Rules card every year (in recent years it has appeared in April). Only hands printed on the current year's card can win. Everyone at a table plays the same card. A table may agree to play another publisher's card; the rules of play in this file still apply, and OOTT never compares or ranks cards.

Each line shows its value and whether it is exposed (X) or concealed (C). Parenthetical notes on the card define what a line allows; read them.

Colors on the card mean how many suits, never which suit. A line printed in one color is one suit, any suit; two colors, any two suits, in any order; three colors, all three. Winds and Flowers are printed in a color but belong to no suit and are not counted when working out how many suits a line takes. A Dragon is different: a Dragon printed in the same color as a number group binds to that group's suit (T-4), and a Dragon printed in a color no number group on the line wears is the opposite dragon. When the line says "Any Dragon", any dragon may be used regardless of its color. Words on the card override colors: "Any 1 Suit", "Any 2 Suits", "Matching Dragons" (the card's own wording; the dragon that pairs with the suit, T-4) and "Any Dragon" (any dragon at all) say exactly what they say. OOTT uses "Matching Dragon" and "Any Dragon"; "Opposite Dragon" on a card means a dragon that does not match, so OOTT never uses that phrase for the matching pairing.

A player may change the hand they are building at any time, so long as any exposures already on the rack fit the new hand. Until the first exposure, nothing is committed.

Consecutive Runs. A run may begin on any number only where the line's parenthetical says any consecutive numbers (or any so-many consecutive numbers); where it says these numbers only, only those numbers. Read the parenthetical (K-2). Soap-as-zero never joins a run (T-5).

Reading a line, in order. First the colors: how many suits the line takes, and which groups share a suit (K-3). Second the parenthetical: what it allows and what it forbids, and the mistake it is guarding against, because this is where hands go wrong. Third the X or C and the value (K-2). Only then the groups themselves, left to right.

How a line is printed. The card prints each group as one unbroken block of characters and separates groups with a space. A run, the year, NEWS and a block of pairs print with no spaces inside them, so on the card they look exactly like a pung or a kong; the parenthetical and the count of characters tell them apart, never the spacing.

Four seats: East, South, West, North. South sits to East's right, West across, North to East's left. Turn order, the deal and the passing of the East seat all move to the right, which seen from above is counterclockwise: East, South, West, North.

The walls are consumed in the opposite direction. When a wall runs out, the player to the left pushes out the next wall: East's wall, then North's, then West's, then South's. Seen from above that is clockwise.

Choosing East: away from home, roll two dice; highest total is East (tied players roll again, by custom). At home the host is customarily East first. After each hand, whether won or a wall game, the East seat and the dice pass to the right.

All tiles are washed face down. Each player builds a wall two tiles high and nineteen stacks long (38 tiles) against the back of their own rack. Four walls of 38 make 152. A set with extra tiles (blanks) makes walls of 20 or 21. Note: the American wall is built against each rack, not as a free square in the middle of the table.

Breaking the wall: East rolls two dice and counts that many stacks along East's own wall from the right end. Those stacks are pushed back against East's rack, to the right, and are the last tiles drawn. Dealing begins from the first stack to the left of the count.

The deal: East takes the first four tiles (two stacks), then the player to East's right, then across, then to East's left, each taking four. Three rounds of this gives everyone 12. Then East takes the first and third tiles of the top row of the next stacks; the player to East's right takes the first bottom-row tile; across takes the next top-row tile; the player to East's left takes the next bottom-row tile. East now holds 14 and everyone else 13.

Who lifts each group of four is a table convention, not a rule: at some tables each player takes their own, at others one player deals them out. Settle it before play.

Tile counts are checked before the Charleston and again after it. Thirteen tiles must be in or on the rack at all times during play (14 for East before the first discard, and for any player between drawing and discarding). What happens when a count is wrong is in DH-9.

A tile knocked over in the wall goes back face down in the same place it came from, never elsewhere.

If the wrong player takes the East seat and it is noticed after the hand has begun, that hand is played out. The next hand goes back to the rightful East, and the round continues, the player who took East in error being skipped when their turn as East would have come.

Positions for a Bettor's disk: East is 1, the player to East's right is 2, across is 3, to East's left is 4.

After the deal and before East's first discard, the players exchange tiles. The first Charleston is compulsory, even for a player whose dealt hand is already set.

First Charleston, in order: pass three tiles right, three across, three left. All passes are face down and all four players pass at the same moment; it is not turn by turn. Three tiles must go on every required pass, however precious the hand; the blind pass exists for that jam. You pass your three before you look at the three arriving.

Blind pass: on the third pass of either Charleston (the first left, the last right) a player who cannot spare tiles may take one, two or three of the tiles arriving and pass them straight on without looking. More than one player may blind pass. A blind pass is allowed on the last pass of either Charleston; "second Charleston only" is wrong.

Second Charleston: optional. Any one player may stop it, without giving a reason, after the first left pass and before anyone has looked at tiles received in the second Charleston. Once it has started and tiles have been looked at, it is completed. Order: three left, three across, three right, with the blind pass available on the last right.

Courtesy (optional) pass: after the first Charleston, or after the second if it was played, each player may exchange 0, 1, 2 or 3 tiles with the player opposite. The player who wants fewer sets the number; if either wants none, none cross. It is always the last pass of the Charleston.

A Joker may never be passed. A passed Joker is handed back; the passer still owes three tiles, so another goes in its place.

Wrong count during the Charleston: the hands are thrown in and the deal is replayed. One exception: if the player to East's left is a tile short after the deal or the Charleston, that player alone may take the next wall tile, and only before East's first discard.

A hand cannot go dead during the Charleston. The game has not begun.

A player who has Mah Jongg during the Charleston cannot stop the passing on that account; the first Charleston is completed regardless. Two exceptions belong to East: a Heavenly Hand is East dealt a complete hand, the Charleston is waived and East wins immediately; an Earthly Hand is East completing a hand during the Charleston and declaring it the moment the Charleston ends, before the first discard. Both are paid as self-picked (SC-3).

If every player wants to blind pass on the same pass, the player with the most tiles to spare passes one or two and says "I owe you", the debt travelling around the table and settled by the first passer from the last pass. If nobody has a tile to pass, the Charleston ends and play begins.

Flowers in the Charleston are a matter of strategy, not rule: OOTT teaches holding them. The rule permits passing them.

Advice, not rule: passing two or three of a kind, matched dragons or winds, or more than one Flower helps another player's hand. Keep singles and pairs you need; let go of what a Joker could later fill.

The game begins when East discards. East holds 14 after the Charleston and discards without drawing. If another player throws first, they take it back and East throws; if another player draws from the wall and discards first, the hand is thrown in and redealt.

A turn is: draw one tile from the open end of the live wall, then discard one tile face up to the centre, naming it aloud correctly. Play passes to the right.

Racking is not required. A drawn tile may be discarded at once. A tile is racked when it sits on the bottom ledge of the rack and leans against the back, with the other tiles; tapping or clicking the rack with it, touching it, or holding it against the rack is not racking. Racking matters because it closes the calling window (C-5) and is the precondition for a Joker exchange (J-6).

You are committed to a wall tile once you have moved it.

A discard is committed once it is fully named or has touched the table, whichever comes first. It cannot be taken back and cannot be used for a Joker exchange. Down is down. A partial name does not commit.

Drawing out of turn: no drawing, and no looking at, the next tile before it is your turn (the card's own line is "no picking or looking ahead", printed since 1956 according to OOTT's fact-checked Learning Guide; the League handbook files the offence as "picking out of turn"). It makes the hand dead (DH-2 (h)). If the tile has not been racked and another player notices at once, it goes back in the wall. Once racked it stays with the dead hand. If it is discarded, that discard is a dead tile that can be called only for Mah Jongg, and then the discarder pays four times the value of the hand.

Discarding before drawing, which the League handbook calls "picking ahead" (rule 15(g)), leaves a 12-tile hand, a wrong count and a dead hand (DH-2 (g)); the count is the explanation, the handbook says only that the hand is dead. Draw first. Exception at the very start of play: a player other than East who discards before picking on the first turn may take the discard back.

Drawing from the wrong wall or the wrong end of a wall makes the hand dead once the tile is racked; the tile stays with the dead hand and the other players continue from the right place (DH-2 (i), (j)). If more than one player has drawn from the wrong end, the hand is thrown in. A player who pushes out the wrong wall, or pushes out a wall early so that someone draws from it, takes the dead hand.

Discarding a Joker: the player may say "Joker", "same", or the name of the previous discard. A discarded Joker is dead the moment it lands (J-3).

Courtesy pause: after a discard, pause a beat before the next player draws, so the table can call. The rule sets no length; the pause is etiquette. OOTT teaches a count of three.

"Wait" or "hold" may be said to stop play while you decide. It is not a call. If the player next in turn calls in the meantime, the tile is theirs.

Any player may call the most recent discard to complete a pung, kong, quint or sextet of like tiles in an exposed hand. A discard may never be called for a single or a pair, except as the fourteenth tile that completes Mah Jongg, in an exposed or a concealed hand.

A call is one word: "call", "take", "I want that". Nobody announces "pung" or "kong"; the tiles laid on the rack say what was made. Saying the set type is optional chatter, never required.

Only the most recent discard is callable, and only by a player other than the discarder.

When the same tile is thrown twice in quick succession, a claim takes the second one. The first is dead.

The calling window closes when (a) the player to the discarder's right has drawn and racked or discarded, (b) another player has begun a Joker exchange, or (c) Mah Jongg has been declared. After that the discard is dead.

The called tile goes on top of the rack, never into the hand. A caller is committed once the called tile is racked, sitting on the bottom ledge of the rack and leaning against the back (P-3), or once tiles have been exposed from the hand. Touching, lifting or holding the tile does not commit the caller. Before that moment a call may be withdrawn.

The completed set is exposed face up on top of the rack and stays there for the rest of the hand. Exposures need not be laid in card order; a space between exposures is courteous.

Same-turn adjustment: until the caller discards, the exposure may still be changed (pung to kong and back, Jokers added or removed, tiles rearranged around the called tile). The window also closes if the caller completes a Joker exchange that turn. After that the exposure is locked for the hand. Nothing may ever be added to or taken from an exposure on a later turn, and a discard can never be called to grow an existing exposure.

Priority between callers:

• A call for Mah Jongg always beats a call for an exposure, even if the exposure caller has already laid tiles down.

• Between two calls of the same kind, the player next in turn after the discarder has preference. An exposure already on the rack from earlier in the hand earns no priority.

• The League's "unless another caller has exposed" clause is a timing exception: if the next-in-turn player is slow and the other caller has already exposed tiles from the hand for this call, that caller keeps it. Touching, lifting or holding the discard does not shut out the next-in-turn player; a discard that is fully racked, sitting on the bottom ledge and leaning against the back of the rack (P-3), commits the caller and shuts the next player out (C-6).

• Two calls for Mah Jongg: next in turn wins; if that player's Mah Jongg is wrong the tile passes to the other claimant.

• If a tile is called for Mah Jongg in error while another player wanted it for an exposure, it stays with the dead hand.

A call takes the turn. After exposing, the caller discards, and play continues to the caller's right. Players sitting between the discarder and the caller lose their turn.

A call the caller cannot legally complete (a lone tile, non-identical tiles, a set that fits no line) is an incorrect exposure and the hand dies when it is called dead (DH-2 (c), (d)). If the set is legal but fits only a different line, the player may play toward that line (K-4).

Once Mah Jongg has been declared and shown, no earlier discard may be called for anything.

A Joker may replace any tile (number, wind, dragon or Flower) in a pung, kong, quint or sextet, and nowhere else. Never in a single, never in a pair, never in NEWS, a year, or a run of different tiles.

A Joker may never be passed in the Charleston (CH-6).

A discarded Joker is dead. It can never be picked up, called or traded for, by anyone, by any means. The single wrinkle is a misnamed Joker (MN-4), and even there the Joker is not truly claimed; the penalty is paid regardless.

Joker exchange (redemption): a player holding the natural tile that a Joker stands for in any exposure on the table, their own included, may swap the natural in and take the Joker. Only a natural goes in for a Joker; a Joker is never exchanged in for a natural.

Timing: on your own turn only, and only after you have drawn and racked, or called and exposed. An exchange made before that leaves the hand short and dead. As many exchanges as your tiles allow may be made in one turn.

Procedure: announce the exchange, hand the natural to the owner of the rack, who makes the swap and hands the Joker back. Never touch another player's rack. If the natural touches the table with no announcement, it is a discard and the Joker stays put.

You may not redeem a Joker and then use it to call the discard just thrown. Make the call first.

A wrong tile placed in an exchange can be corrected without penalty until the player discards. After the discard, the hand with the incorrect exposure is dead.

A tile that has been fully named or has touched the table cannot be used for an exchange (P-5). A discarded tile called from the centre can only be used for an exposure or Mah Jongg, never for an exchange.

While a player is in the middle of an exchange, nobody may call a previous discard, even if the exchanging player has not yet racked.

A hand that used a Joker and later exchanged it out, holding no other Joker, is jokerless (SC-4). Jokerless is judged on the final fourteen.

The Finesse: if the last move before declaring Mah Jongg is a Joker exchange, from any rack including your own, the win is self-picked and everyone pays double. A Finesse win is never jokerless, because the redeemed Joker joins the hand.

Jokers on a dead hand: Jokers in exposures made correctly before the hand died stay on the rack and stay redeemable by live players. The exposure that was in error goes back to the sloped front of the rack, Jokers and all, and nothing in it can be redeemed. It is the erroneous set that goes back, not the most recent one. Until a bad exposure is noticed and the hand is called dead, its Jokers are not redeemable in the interim. A concealed hand exposed in error returns everything and nothing is redeemable.

Keep Jokers visually distinct on the rack (etiquette).

A concealed hand (marked C) is completed without any call for an exposure. The one tile that may be called is the fourteenth, for Mah Jongg. A concealed hand may therefore win on a discard or on a self-draw; "own pick only" is wrong.

Calling a discard and exposing a set takes a player off any concealed hand. The hand is dead when another player can see that a concealed line was being played and tiles were exposed (DH-2 (f)). If the exposed set fits an exposed line, the player may play toward that line instead; nothing is dead until it is provably dead.

A concealed hand may switch to an exposed hand at any time. An exposed hand may switch to concealed only if no exposure has been made.

A player building a concealed hand may redeem a Joker from any exposure on the table. A Joker exchange is not an exposure and does not break concealment; the League's ruling is that a Joker may be replaced "by any player".

Mah Jongg is declared when the fourteenth tile, drawn or called, completes a line on the current card. The whole hand is shown on top of the rack and every player verifies it against the card. The game ends.

Nobody throws in or exposes their own hand until the winner's hand has been verified.

The winner announces the value of their own hand, including that it is jokerless if it is. The announced value stands even if someone later points out a higher one.

Mah Jongg declared in error:

• Corrected at once, before the hand is exposed and before anyone else disturbs their hand: no penalty, play on.

• Declared on a discard, tile placed on the rack or tiles exposed, then found short: the player may change the declaration to a call for an exposure. No penalty.

• Hand exposed in part or whole with all other hands intact: the declarer's hand is dead. The exposed tiles go back to the rack. The dead hand stops picking and discarding and pays the eventual winner the full value of the winning hand. Jokers in exposures called correctly before the error stay redeemable; a concealed hand returns everything (J-13).

• Cascade: if one other player has thrown in, play continues between the two intact hands; if a third then goes dead, that player pays the remaining player double the value of the hand they were attempting. If two others threw in, the false declarer pays the one player who did not double the value of that player's hand. If a player destroys the wall before the error is discovered, that player pays each remaining player the lowest value on the card. If three hands are dead for reasons other than a false Mah Jongg, the last player throws in and nobody is paid.

Tournament practice (convention, not the home rule): a false Mah Jongg is dead on the spot with no chance of forgiveness; at a social table OOTT's Table Live lets the other players overrule and play on.

Each line's value is printed on the card. Payment is in those units (cents at most tables, points in tournaments).

Win on a discard: the discarder pays double the value; the other two players pay the value as printed.

Self-picked win: all three players pay double. Self-picked means the winning tile came from the wall, or from a Joker exchange (Finesse, J-12), or the hand was dealt (Heavenly) or completed in the Charleston (Earthly, CH-9). Heavenly and Earthly are self-picks, not an additional double.

Jokerless: a hand that permits Jokers and is completed with none doubles its printed value, and then the normal schedule applies. So a jokerless discard win costs the discarder four times and the others twice; a jokerless self-pick costs everyone four times.

The jokerless double does not apply to the Singles and Pairs section, whose values already build it in.

A dead hand pays the winner the full value of the winning hand, at the single rate.

Wall game: nobody pays (W-1).

Confirm doubles before play. Some tables drop the Heavenly and Earthly doubles or play only the jokerless double; the schedule above is the League's.

Tournament point scoring. The League publishes no tournament schedule; the sheet most tournaments play by scores this way, and so do OOTT's tournament tables.

• The winning hand scores its card value.

• Self-pick: +10. A Heavenly Hand earns no self-pick bonus.

• Jokerless: +20, never on Singles and Pairs.

• Wall game: +10 to every player at the table; a hand that went dead, or was declared dead, scores zero, taking neither the wall points nor a penalty.

• The player who throws the winning tile: minus 10 if the winner had no exposure or one, minus 20 for two, minus 25 for three or more.

• Misnaming a discard that gives an opponent Mah Jongg: minus 25 to the discarder (the tournament form of MN-3).

• Looking at a blind-pass tile: minus 10.

• Mah Jongg declared in error with any tile exposed: dead, zero. If the three others then expose, all four score zero; if one keeps her hand intact she scores 10 and the rest zero; if two or more are intact the game goes on.

• A game not finished at time: zero for everyone.

• A round is four games in about an hour (50 to 55 minutes at the director's discretion); table rotation after each round.

The director's ruling is final at any outside event.

East pays and collects like every other seat. There is no dealer bonus and no dealer penalty in the League's schedule.

There is no separate concealed-hand bonus. A concealed line's higher value is printed on the card and that is the whole reward.

Worked example, for products: a 50 line, jokerless, self-picked (including Heavenly or Earthly) pays 50 x 2 x 2 = 200 from each player, 600 in all. Not 400 each: Heavenly is the self-pick, not a third double.

A hand is never dead on its own say-so. A player may not declare their own hand dead. A hand is dead only when another player calls it, on evidence visible to the table, and the call stands.

Causes:

• (a) Wrong number of tiles after East's first discard: fewer than 13 or more than 14.

• (b) A Joker exchange made before drawing and racking, or before calling and exposing.

• (c) An incorrect exposure: tiles that do not form a pung, kong, quint or sextet of like tiles (NEWS, a year, mixed tiles, a lone tile).

• (d) Exposures that match no hand on the current card.

• (e) An unwinnable hand: the exposures show a hand needing singles or a pair to finish, and three or more of the four needed tiles are already discarded or exposed.

• (f) Exposures on a concealed hand.

• (g) Discarding before drawing (a 12-tile hand).

• (h) Drawing out of turn, once the tile is racked.

• (i) Drawing from the wrong wall, once racked.

• (j) Drawing from the wrong end of the wall.

• (k) Calling a discard for an exposure on a wrong name (MN-2).

• (l) Declaring Mah Jongg in error with tiles exposed (M-4).

• (m) A wrong tile in a Joker exchange not corrected before the discard (J-8).

• (n) Pushing out the wrong wall, or a wall too early, so that a wrong tile is drawn.

Evidence: a hand may be called dead from what is visible, meaning the exposures, the discards and the tile count. Counting how many tiles a player holds is allowed and needs no look at their faces, so a wrong count is callable. A hand may never be called dead by guessing at the identity of concealed tiles. Limit: only an exposed hand may be verified and called dead. A fully concealed hand cannot be called dead from the discards: no one knows what that player is going for.

Quietly dead: a hand that is in fact dead but that nobody has called keeps its seat, keeps drawing and discarding, plays defence and says nothing. The player must not announce it. Nobody should ever know. It cannot win.

The challenge: any other player may call a hand dead at any time, even out of turn. A question or a comment about whether a hand is dead counts as a challenge. The conversation is between the challenger and the challenged only; the others stay silent. The challenged player may accept, and stop, or disagree without revealing anything, and play continues.

Settlement: a disputed call is resolved at the end of the hand when the tiles are shown. Whoever was wrong at the moment of the challenge pays the other player 50 (cents or points), on top of whatever is paid to the winner. A wrong challenger pays; a wrong denier pays.

Declared dead: once a hand is confirmed dead, that player is disqualified for the rest of that hand only: no draw, no discard, no call, no win, and silent to the end. They keep their tiles on the rack and pay the winner full value (SC-6). Jokers on the rack follow J-13. The next deal starts everyone fresh.

The two states are not a contradiction. Quietly dead keeps playing; declared dead stops. You cannot be disqualified by something only you can see. Either state lasts the current hand, never the round.

Wrong tile counts by timing:

• Before or during the Charleston: hands thrown in, redeal (CH-7, with its one exception for the player to East's left).

• After East's first discard: that hand is dead. If two players have wrong counts the other two play on; if three do, the hand is replayed.

Advice to a dead hand playing defence: a Joker is the one perfectly safe throw, since nobody can ever call it; a tile already sitting uncalled in the discards is next safest; a tile whose naturals are mostly showing is safe when three of four are visible. Count naturals, not the size of an exposure: Jokers standing in a set do not use up the real copies.

A tile cannot be claimed until it is correctly named, except for Mah Jongg. A misnamed discard can be called for nothing but Mah Jongg. If the name is corrected before anyone acts, there is no penalty and the window opens on the corrected name.

Called for an exposure on the wrong name: the caller's hand is dead. The misnamer is not penalized. The burden is on the caller to look as well as listen.

Called for Mah Jongg on the wrong name: the game stops. The claimant needed the tile by the name that was called and the Mah Jongg stands. The misnamer alone pays four times the value of the hand. The other two pay nothing. This is "paying for the table".

A discarded Joker called by a tile's name: the caller does not technically have a claimed Mah Jongg, since a discarded Joker can never be claimed, but the misnamer still pays four times the value and the game ends. The player collects. This nuance is Joker-only.

A wrong name changes nothing about priority. The misnamed tile goes to the player who needs it for Mah Jongg, and that player has to be next in line: if two players need it, the one next in rotation after the discarder gets it, as in C-9. There is no competing exposure claim on a misnamed tile: it can only be called for Mah Jongg (MN-1), and a player who calls it for an exposure is dead (MN-2).

When the wall is exhausted with no Mah Jongg, the hand is a wall game. Nobody pays. The tiles are washed, the walls rebuilt, and East passes to the right. OOTT's games call it "a wash".

Tournament scoring: 10 points to each player; a hand that went dead or was declared dead, a hand dead for a false Mah Jongg included, scores zero, taking neither the wall points nor a penalty (SC-9).

A Bettor who bet on a wall game collects the lowest value on the card from each player (B-4).

Hot wall, cold wall, mushing (reshuffling the remaining wall) and atomic hands are house rules, not League rules, and are not played in tournaments.

A fifth player may bet on the player most likely to win, after the Charleston and before East's first discard, by writing the name or using the betting disk (D-10). A bet on a wall game is allowed. The bet is not disclosed and may not be changed during play.

The Bettor stays silent throughout, even on seeing an error, and pays or receives exactly as the player bet on. Interfering with play cancels the bet.

Payment: if the player bet on self-picks, winner and Bettor each receive double from every player; on a discard win only the discarder pays double, the others single, and the winner shares with the Bettor. The League recommends all money goes to the winner first, who then splits it. A Bettor who chose wrong pays the winner what the chosen player pays.

A correct wall-game bet collects the lowest value on the card from each player.

Pie is a social tradition, not a tournament rule. Confirm before play.

Two-handed: players sit opposite, each builds their own wall and the wall to the right; the empty seats take no hand; no Charleston; East discards to start. Three-handed: four walls are built, the seat without a player takes no hand, each player draws thirteen, and East a fourteenth; no Charleston. Four-handed with a pivot: the original East changes seats with the player to the right after each round of four hands and takes the dice. Five- and six-handed: four play, the others sit out or bet; after being East a player steps out for the next.

Kards: the same 152 faces on playing cards, dealt like cards (four at a time then one, East 14), Charleston as usual in a four-handed game and omitted in two- or three-handed, scored by running points from 1,000.

Towers (also Stacks, Pyramids, Houses): a house variant OOTT plays on Table Live. No walls at first; 13 tiles each (East 14); seven face-down towers of three per player; a player trades three unwanted tiles face down to the pool for the next tower, at least three times and at most seven. Legal stopping points are 3, 4, 6 or 7 towers, never 5 (towers 1 to 3 stand for the first Charleston, 4 to 6 for the second, all or nothing, and 7 for the courtesy). Pool and unused towers are washed into the wall, which comes back to 99, and ordinary play follows. A Joker may arrive in a tower, and a Joker may be traded into the pool; the Charleston's Joker ban does not apply because a tower is not a pass to a person.

Blanks: a house variant with two or four blank tiles washed in from the start. A blank is exchanged for a tile from the discards in the centre and for nothing else: never for a Joker in someone's exposure and never for a discarded Joker. Walls run 20 stacks on two (four blanks) or one (two blanks) of the four. Trading mechanics vary by table. Not League play.

Siamese: not a League game. Gladys Grad originated it (Florida, 2015) and her rules govern. One player plays two hands against one opponent. Per Grad's rules: East takes 28 tiles and the opponent 27; no Charleston; concealed tiles move freely between the two racks, exposures are fixed to the rack they were made on; the first Mah Jongg does not end the game, the declarer discards from the other hand and play goes on until a second Mah Jongg or the wall runs out; Jokers in a declared hand are not redeemable; between two callers the nearer in turn wins, first or second Mah Jongg alike. Messy Mahj is OOTT's Siamese drill and follows Grad.

The Black Dragon: a house addition in Order of the Tile's printable decks, not League play. Every one of the fourteen decks carries four Black Dragons, 152 cards becoming 156, and every deck's Card carries hands 11 and 12 written around the tile. At our table today the Black Dragon is a dragon and spells the letter B; the Soap stays the Dots dragon and the only zero (T-4, T-5). Two house rules of our own, marked as ours on the guide card: the Sting, five points per Black Dragon left in a hand when someone else wins; Black doubles, a kong of Black Dragons pays double. The wall takes the four extra tiles dealt out with the rest. The site's games deal 152 tiles and no Black Dragon today.

Name every discard clearly, for the farthest player.

Pause after a discard so the table can call.

Do not delay a draw or a discard on purpose.

Do not look at, touch or comment on another player's tiles or hand.

Give nothing away by word or expression about whether a discard helps you.

Before the second Charleston, someone at the table asks whether anyone wants to stop. It does not have to be East; the question has to be posed by the table. This is etiquette, not a rule; the rule is CH-4.

Hand a Joker-exchange tile to its owner; never place tiles on another rack.

Say a discard aloud even when a game names it for you.

Tell the table if you step away.

The four pillars: fairness, accountability, integrity, respect.

Settle a dispute by the card and rules the table agreed before play; for most tables, and in OOTT's games, that is the current NMJL card and the League's rules.

Pace: the course's target is about eight seconds a turn; a beginner's pace is welcome, a glacial one is not; narrate a longer pause.

Tile names are spoken only when discarding; nobody announces what they collect or need, and nobody says a card pattern aloud.

"Looking" may be said when you are one tile from Mah Jongg; it is a courtesy, not a requirement.

Declining the second Charleston or the courtesy pass is a legitimate choice, never rude.