Dragon sequences

Class twelve. Dragon sequences. But first, a warning about the word "dragon." In class eleven, dragons meant red, green, white: the three honour tiles. Today, "dragon" means something completely different. Today a "dragon" is a nine-tile sequence that runs from one to nine. Three sheungs stacked together (one-two-three, four-five-six, seven-eight-nine) forming a full nine-tile run. This has nothing to do with the dragon tiles. I'm sorry the word is overloaded. Nobody can explain why mahjong did this to itself. You just have to hold both meanings in your head.

The simpler version first. A "Pure Dragon" is a full one-through-nine sequence all in ONE suit. Three sheungs: one-two-three bamboo, four-five-six bamboo, seven-eight-nine bamboo. Or all in circles. Or all in characters. That's a Pure Dragon. If any of the three sheungs were claimed from a discard (meaning at least one of them is exposed) the whole thing is "Pure Dragon Exposed," ten tai. If all three sheungs were built in your own hand without any claims, it's "Pure Dragon Concealed," twenty tai. Double, for keeping it hidden. You'll see this pattern across all of mahjong: exposed is usually half of concealed.

Now the trickier version. A "Mixed Dragon" is a one-through-nine sequence where the three sheungs come from THREE DIFFERENT SUITS. But under LRC rules (the rules we play) not every three-suit arrangement counts. Only two specific ones score. The first, called "MD1," is one-two-three bamboo, four-five-six character, and seven-eight-nine circle. The second, called "MD2," is one-two-three circle, four-five-six character, and seven-eight-nine bamboo. See the pattern? In both arrangements, characters always hold the four-five-six middle. If your "mixed dragon" puts the middle in bamboo or circle, it doesn't score as a mixed dragon under LRC. The engine won't give you the points. It's a strict rule. Memorise the shapes. MD1: bamboo, character, circle, low to high. MD2: circle, character, bamboo, low to high.

Mixed Dragon values follow the same exposed-or-concealed split as Pure Dragon, but they're HALF the numbers. Mixed Dragon Exposed is five tai per group. Mixed Dragon Concealed is ten tai per group. And "per group" matters. It's theoretically possible, though very rare, to build TWO Mixed Dragon groups in the same hand at once. That'd score two times ten, twenty tai. I've never seen it in a live game. The engine counts them anyway.

Let me show you a real Pure Dragon. You're going to build a full one-through-nine run in bamboo, all concealed, and I want you to see the stack it creates.

Count with me. Base five. You drew your own winning tile, so Self-Pick one. Six. Your hand was entirely concealed, and you won by drawing, so "Self-Draw Concealed" fires for ten. Sixteen. Your bamboo sequence one through nine in one suit is "Pure Dragon Concealed," twenty. Thirty-six. Your hand has no winds or dragons, so "No Honours" fires for one. Thirty-seven. One flower on the side, one more. Thirty-eight. And because your pair is a pair of fives, a good eye, two more. Forty. Forty tai, clean. Almost half of it came from the Pure Dragon alone. Notice how a single composition rule can double the size of an otherwise ordinary hand.

That's class twelve. You know what a dragon sequence is, and you know the two LRC arrangements for a Mixed Dragon. Class thirteen: neighbours, brothers, and sisters. The smaller but more common shape patterns that show up in half the hands you'll ever play.