Sichuan Mahjong · 1 fan

Root (Gen) in Sichuan Mahjong: How It Scores, Examples and Odds

In Sichuan mahjong, a root (根, gen) is worth 1 fan each: when you win, every kind of tile with all four copies in your own hand (tiles in hand plus your punged and konged sets) adds a root. You can have several, one fan each, added straight to everything else. Sichuan has few scoring patterns, and the root is the fan that most often turns a small hand into a bigger one.

The rules for roots

• One kind with all four copies in your hand: four in hand, a kong, or a pung with the fourth copy kept in hand
• No kong needed: four copies split across sets (say two runs and a pair) still count
• One root per kind — as many kinds, as many roots
• In Dragon Seven Pairs the first four of a kind is part of the hand, so only a second one adds a root

Where roots come from

Kongs: the usual root

Exposed, upgraded or concealed — a kong is four tiles, so it always brings a root when you win.

No kong: four tiles kept in hand

After a pung, drawing the fourth copy doesn't oblige you to upgrade; keeping it for a run still counts as a root:

Not konging means nobody can rob the kong and you show less; the cost is no kong money and no replacement draw (no chance of a win after a kong).

How roots are scored

Fan add up, and each extra fan doubles the payment, up to the cap of 4 fan. The hands below are scored live by the same code the game uses (the self-draw bonus and kong payments come on top).

Common combinations:

How it relates to other hands

• Win after a kong: self-drawing your kong replacement — the kong itself is a root, so it's always at least 2 fan.
• All Pungs: punging and later upgrading to a kong is common, so All Pungs often carries a root.
• Dragon Seven Pairs: four of a kind in seven pairs makes the dragon; the first one isn't a root.
• Pure One Suit: with one suit concentrated, four of a kind comes together more easily.

Root odds

In 40,000 hands of normal computer play there were 0.7 kongs per hand on average, and 19% of all wins carried a root — the most common fan apart from plain hands. Exactly one root: 17% of wins; two or more: 1.5%. Wins with a root averaged 1.2 fan, with each payer paying 2.6 units.

Source: 40,000 hands of computer play on this site (four normal-level players, 115,067 wins in total), cap 4 fan.

To kong or not

• Concealed kong: almost always. Each player pays 2 units on the spot ("rain"), the root still counts, and you get a replacement draw.
• Upgraded kong: check the table first — someone may be waiting on that tile. If they rob it, you lose the kong money and pay for their win.
• Exposed kong: the discarder pays 2 units. With three in hand and the fourth discarded, a kong means root plus kong money — but you can no longer use those three for runs.
• Don't kong when going for Seven Pairs: a kong breaks concealment; four kept in hand make Dragon Seven Pairs.

To try it, open a table of online Sichuan mahjong — the computers play blood battle with you and count the fan for you.

FAQ

How many fan is a root?

1 fan per root, so two roots are 2 fan. Totals above the 4-fan cap count as the cap.

Does it count without a kong?

Yes. As long as all four copies are in your own hand (four in hand, or a pung with the fourth kept), it's a root.

Do you still get a root after konging?

Yes. The kong money is paid on the spot; when you win, the kong also counts as a root.

Do the four tiles in Dragon Seven Pairs count as a root?

The first four are part of Dragon Seven Pairs and don't count again; a second set of four adds a root.

Related hands

Win After a Kong 1 fan Self-draw the kong replacement: 1 fan plus the root, at least 2 fan. Examples, who pays, and the odds per kong. Dragon Seven Pairs 3 fan Seven pairs with four of a kind — 3 fan. Examples, how roots work, double / pure dragon seven pairs, and how often it happens. All Pungs 1 fan Four pungs and a pair — 1 fan. Examples, 2-5-8 / golden hook / pure-pungs combos, and how many pairs you need to go for it.