Matching Dragons, Opposite Dragons
Dragons are the one place a colour on the card names a suit. Miss that and half the card stops making sense.
On this page
An opposite dragon is a dragon printed in a colour your hand is not using, which means it must not be that suit's dragon. It is the one place a colour on the card points at a suit, and it is deliberate, not a misprint.
You've learned that the colours on the card say how many suits a hand needs, not which ones. Then you meet a line with a dragon in it, and that rule appears to break.
It doesn't. Dragons are the single exception, and once you know the shape of it, a whole category of lines becomes readable.
Each dragon belongs to a suit
Commit that to memory before anything else. Everything below is built on it. There are four of each, twelve in all, and the count matters less than the pairing.
The white dragon and the dot suit are both circles and blanks — the plainest tiles in the set. Red and green then fall out by elimination, and red 中 sits on the crak tile's own red character.
Same colour means matching
When a dragon is printed in the same colour as the numbers around it, it has to be that suit's dragon.
So a line printed all in one colour, containing numbers and a dragon, is asking for one suit throughout — and the dragon in it is the one that goes with whichever suit you chose. Pick bams, and it's green. Pick craks, and it's red.
You still choose the suit. The dragon just follows you.
A different colour means the opposite
Now the part that trips people. When the dragon is printed in a colour the rest of the hand isn't using, it must not match.
| The dragon is printed… | Which means |
|---|---|
| In the same colour as the hand | Matching dragon — that suit's dragon |
| In a colour the hand isn't using | Opposite dragon — deliberately not that suit's |
"Opposite dragon" is a real term you'll hear across the table, and it catches people out because it looks like a misprint. It isn't. The different colour is doing exactly what colours always do on this card: saying this belongs to a different suit from the thing beside it.
Choosing bams for your numbers and then reaching for green dragons because green feels like the bam colour. If that dragon was printed in a different colour from your numbers, the green one is exactly the one you can't use.
Where soap stops being a dragon
The white dragon has a second job, and it's worth separating cleanly.
- As a dragon, it's the dot suit's matching dragon.
- As a printed 0, it isn't a dragon at all — it's a zero, and a zero has no suit.
Soap is a zero only where the card actually prints a 0. It is not a floating zero you can drop into a hand that wants one, and it is not a ten. And because zeroes are suitless, a 0 can be printed in any colour at all without that colour meaning anything — read a suit out of it and you're reading a signal that was never there.
Jokers, while we're here
Dragons take jokers exactly like any other tile: fine in a pung, kong, quint or sextet, never in a pair or a single. The dragon's suit pairing changes which dragon you need. It changes nothing about where a joker may sit.
When you have read it all: the rules workbook, 105 questions with an answer key that cites the rule behind every answer, $19.
Where this comes from
The dragon-suit pairings and the matching/opposite distinction are explained on the back of the National Mah Jongg League's card, and are confirmed by Tom Sloper's rules FAQ and by I Love Mahj's card guide independently. The limits on soap as a zero follow the official rulebook via Sloper, who dates the current wording to 2018.
No hands, values or card arrangement are reproduced here. You need your own current card.