Long backgammon rules

What long backgammon is

Long backgammon — nardy in its own tradition — is one of the two main branches of the game. There is no hitting here: a checker does not knock an opposing one off the board, it simply cannot land on an occupied point. That removes the element of the lucky strike and turns the game into a race with positional blocking.

Short backgammon — the game most English speakers mean by “backgammon” — runs on different physics: the players move toward each other, a lone checker can be hit, and a closed point needs two checkers, because the second one is what protects against the hit. ProNardy implements the long game only; the full comparison is in “Long vs short backgammon”.

The board and the starting position

The board has 24 points. Physically it is the familiar backgammon board of four quadrants, but unlike the short game the points form one shared ring that both players travel in the same direction. Each player starts with all 15 checkers on a single starting point — the head. The two heads sit diagonally opposite, exactly 12 points apart: point 24 for White, point 12 for Black.

A player’s home board is the last six points of their route: points 1–6 for White, 13–18 for Black. Because the two routes are offset by half a ring, your head is the midpoint of your opponent’s distance, and theirs is the midpoint of yours. Until all 15 checkers arrive, the home board is an ordinary stretch of the route like any other.

The goal of the game

Move all 15 checkers a full lap to your home board and bear them off before your opponent does. There is no hitting: you can neither send an opponent’s checker back nor land on any point holding even one of their checkers. The whole fight is about speed — and about denying your opponent the points they want.

The opening roll

The right to move first is decided by a roll-off: each player rolls one die and the higher number starts; a tie is re-rolled. The winner of the roll-off then rolls both of their own dice again and plays the first turn of the game.

A turn

A turn is two dice. Each number is a separate move: one checker for the sum, or two different checkers for one number each. You may only land on empty points or points already occupied by your own checkers.

• You must play the maximum. If both numbers can be played, both must be played. Declining a legal move is not allowed.
• If only one of the two numbers can be played, play it — the other is lost. If either number can be played alone but not both together, you are obliged to play the larger one.
• If no legal move exists at all, the whole turn is skipped.

The head rule

Only one checker may leave the head per turn. The exception is your first turn of the game: on a roll of 3-3, 4-4 or 6-6 you may take two checkers off the head.

That set of three doubles is not arbitrary — it follows from the geometry of the start. The heads are exactly 12 points apart, so a checker leaving the head runs straight into the opponent’s head on precisely these numbers: with 6-6 it is blocked on the second step of the double, with 4-4 on the third, with 3-3 on the fourth and last. With 1-1, 2-2 and 5-5 it never lands there at all. The second checker is allowed purely so that the remaining compulsory steps can be played.

Doubles

Equal numbers (4-4, say) are played four times instead of twice — four separate moves of four points each. The maximum rule applies here too: you must play as many of the four moves as are legally possible, not as many as you find convenient.

Blocking and the six-point prime

A point holding even one of your checkers is closed to your opponent. Several closed points in a row form a block; six in a row form a prime, which no single die and no sum of two can jump. Because there is no hitting, a point costs one checker rather than two: a prime costs six checkers and leaves the other nine free to play.

You may only complete a full six-point prime while at least one of your opponent’s checkers is still ahead of it — that is, further along their route toward bearing off. Sealing your opponent in completely, with all of their checkers behind the barrier, is not allowed. At the start of a game every opposing checker is still on the head, so a prime right in front of it is forbidden.

How to arrange checkers so that a prime builds itself, and which mistakes cost it, is covered in long backgammon tactics.

Bearing off

You may start bearing off (removing checkers from the board) only once all 15 of your checkers are home, and not a point earlier. Home points are numbered 1–6 from the edge:

• A die bears off a checker from the point of the same number.
• If that point is empty and all higher points are empty too, the checker comes off the highest occupied point below the die.
• While higher points are still occupied you may not “overpay” with a die — play an ordinary move inside your home board instead.
• When a die allows both a bear-off and an internal move, the choice is yours. There is no forced priority either way.

Scoring: Oin, Mars, Koks and Home Mars

Long backgammon has no draws. When the winner bears off their fifteenth checker, the loser’s position sets the price of the win — from 1 to 4 points. The names are transliterated from the game’s own tradition rather than borrowed from the short game, because two of them mean something different here:

The conditions never overlap: a checker in the starting quarter already means “not all home”, so Koks and Home Mars cannot both apply. Mars is the residual case — nothing borne off, the starting quarter fully cleared, the home board not yet complete.

Resigning, the clock and no-shows

Resigning or running out of time does not simply “cost 1 point” — the score is always computed from the final position on the same scale. Resign without having left your starting quarter and it is a koks; resign with all 15 home and none borne off and it is a Home Mars. That closes the “resign cheaply” loophole.

The only result with no position behind it is a walkover in scheduled games: if your opponent does not appear in the room within 10 minutes of the agreed time, the player who showed up takes the maximum — 4 points. If neither player appears, the challenge is voided and nobody scores.