~shunter/ur-game

e7cefcf4bd234320ce43d330e8837d1fa660ac90 — Samuel Hunter 3 years ago 0d0a4e6
Add rules doc
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# The Royal Game of Ur - Rulebook

The Royal Game of Ur was rediscovered by British Archaeologist Sir Leonard
Woolley between 1922 and 1934. British Museum curator Irving Finkel translated
a Babylonian clay tablet and the photographs of another Sumerian tablet to
reconstruct a set of plausible rules for the game.

The Royal Game of Ur is a chance racing board game where two players compete to
run all seven of their checker pieces through the board before the other.

## Pieces

The gameboard is an 8x3 size square board, with two tiles from the top and
botom notched out from the fifth and sixth column of the top and bottom rows.

[TODO graphic of board]

The gameboard has various visual patterns on its tiles, including five rosette
tiles: four on the first and seventh columns of the top and bottom rows, and
one on the fourth column of the middle row.

The gameboard is played with two sets of seven checker pieces: one black, and one white.

Finally, there is a set of four four-sided tetrahedron dice. Each die has half
of their points marked, and half left unmarked, giving each piece a 50-50
chance to roll a mark.

## Setup

The board is cleared and both players are given their set of checkers.
Following Chess standards, the player with the white set is given the dice,
giving them the first move.

## Objective

Each player takes turns rolling dice to move their checkers from the pool,
across the board, and then out of play. The first player who moves all of their
checkers out of play wins.

## Turn

The active player begins their turn by rolling the dice. Sum up all the dice
with a marked side up, and that's the fixed number of spaces a single piece can
move.  An active player may move a checker from their pool to the board, within
the board, and from the board out.

It takes a pip to move from the pool to the beginning of the board, a pip to
move from the end of the board out of play, and a pip to move from one tile to
the next. The player must use all roll pips on a single move.

[TODO show graphic of board, detailing the mirrored route of each player]

A player can then freely move one of their checkers on any of these conditions:

- The piece moves out of play
- The destination tile is empty
- The destination tile is not a rosette (an opponent piece is "captured")

If the destination tile is owned by one of their own checkers, or is a rosette
owned by an opponent checker, a player may not move there. If the destination
tile is otherwise owned by an opponent, a player may "capture" that checker by
moving there, sending the checker back into the opponent's pool.

If a player has no valid moves, they are forced to skip their turn.

## Rosette

There are five rosettes decorated on the game board: two on tiles private to
each of the two players, and one in the middle of the board accessible by both.
A player that lands on a rosette nets an extra turn, and checkers on a rosette
tile may not be captured.