On the outskirts of Ur

In one moment, see Eternity,
A huge world - in the grain of sand,
In a single handful - infinity,
And the sky - in a cup of a flower.

sir william blake

One drop of water ... - a person who can think logically can conclude that the Atlantic Ocean or the Niagara Falls can exist, even if he has not seen one or the other and has never heard of them.
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Sir Arthur Conan Doyle " Etude in Crimson Tones "

Today, I want to support the initiative of the respected Unlimion and talk about the attempt to restore the rules of the game, which is considered to be the oldest known game related to the movement of chips on the board. Boards for this game were found in 1926-1927, the famous archaeologist Sir Leonard Woolley, on the excavations of the ruins of the city-state of Ur in Mesopotamia. The game itself dates back to 2600-2500 BC. Since the name of the game is still unknown, it is named after the city in which it was found.

As is often the case with archaeological finds, quite a lot of sets were found for the game, but how to play them was completely incomprehensible. The set for the game included a board of a very original form, with 7 flat chips for each of the players (one side of each chip was marked with 5 dots), and also a set of 3 playing dice. The bones were also unusual. Each of them was a tetrahedron , two of whose four vertices were painted white. A little later, archaeologist Irwin Finkel found a clay tablet with a set of rules.

However, she did not bring any particular clarity. To read it, in our time, few can, and the ancient chroniclers, apparently, did not particularly bother with the description of the questions that were considered obvious to them. In addition, there is no certainty that the tablet found described the very game. At the same time, the issue of rules was acute, as the British Museum was very interested in selling souvenir copies of the game. Archaeologists have proposed several options that, unfortunately, have one "fatal flaw". These, in many respects, of course, highly respected people, apparently never tried to play by the rules that they proposed. Our compatriot, science fiction writer, board game historian and just a very good man, Dmitri Skiryuk, took this annoying mistake. I will say at once that of all the proposed options for the rules, his version seems to me the most interesting, in the game relation.

Dmitriy's article is a great example of the use of the “deductive method” in real life and would have done honor to Sherlock Holmes himself. In my opinion, he proposed rules explaining practically everything:

• The strange shape of the board and its layout
• Use for playing flat chips
• Using Marks on Chips
• Unusual set of game "bones"

The gameplay of the resulting game is great. Of course it is possible that the ancient Sumerians played it somehow differently, but, in this case, I think that they simply punished themselves. After becoming acquainted with the proposed rules, it is simply impossible to imagine that this game can be played differently.



So, each player has seven chips. The goal of the game is to lead each of the chips along the trajectory shown above, removing them, thereby, from the board. To complete the last move, removing the chip from the board, an “accurate” throw is required. It is easy to see that along the central (common for the players) line, each piece moves first towards the small block, and then in the opposite direction.

In order not to get entangled in the directions of movement, after passing through the “field of transformation” (the extreme cell closest to the player in the small block), the chip is reversed. Chips can “chop” each other, standing on an occupied cell (a felled chip returns to the player’s starting set), but Dmitriy assumes that only identical chips can chop each other - an inverted one cannot “chop” not inverted and vice versa. From myself I can see that this really makes the game more interesting. In some cases, the enemy chips are the target, in others - an obstacle.

At what number of steps the chip can move, determines the throw of the “bones”. Dmitry offers the following interpretation of the results of these shots:

• One pyramid of three fell with a white top up - you can move any piece one square or place one of the start-up chips on the first board field
• Two white peaks up - two cells or placing a new chip on the second cell
• Three white peaks - a move for three cells or a third position in the course of movement on the board
• All the pyramids fell black side up - move to four cells or placing chips on the first in motion "outlet"

A strange set of "bones" is quite meaningful. Instead of three bones with two possible states, it would be possible to use one with four (at least the same tetrahedron painted in 4 colors), but, in this case, all possible results of the throws would be equally probable. In the case of using a set of three dice, one and two-point shots are more likely than throwing three or four points. This fact directly affects the gameplay.

With this interpretation of the moves, the "sockets" make sense. Dmitry assumes that having stopped on such a cell, the player has the right to make an additional move. Throwing away some "fours", you can quickly run through the entire board without giving the opponent even the possibility of a turn! Even throwing out points other than fours, I managed, moving a few chips, to make 3-4 moves in a row. The game turns into a real battle for the "sockets".



Even in this form, the rules are quite playable, but Dmitry went further, trying to explain the markup of the other fields. According to his version, the only reason for using flat chips to play is the ability to install them on each other. But the possibility of "cutting down" enemy chips is also very important tactically. Perhaps it is possible to cut down chips, but not everywhere? Fields with a strange layout with four "eyes" are located in very convenient places, allowing you to "unload" the board, avoiding unnecessary "congestion" in the game. According to Dmitry, on these fields, the chips can be arranged in a column, up to four pieces, but provided that they are all the same color. Similarly, the fields can work with a marking of four groups of five points (recall that one of the sides of each game chip is marked in the same way). On these fields, you can build "columns" of chips of any color, thus locking the enemy figures (only the top chip in the column can walk).

It is clear that here we are entering the realm of assumptions, but with the introduction of these rules, the game literally acquires a new dimension. Additionally, Dmitry introduces a rule that does not allow "to cut down" an inverted chip, standing on the last cell of the board. Since this field "locks" the output of non-inverted chips from the initial fields, in a tactical sense, this rule is also interesting.

Having read about “Ur” for the first time, I set about trying to realize it. In fact, I saw several variants of Seneta , but I could not find a single implementation of Ur. But this game is no less interesting! Technically, the work on the game fully met all my expectations. I had to tinker with the unusual “transformation” of the chips (the chip turns not when installed on the transformation field, but when passing through it) and with the alignment of the chips in the bar. Anyone can look at the history of all these ordeals on GitHub . Almost at the curtain, ZoG delivered his blow:



At the end of the game, as a result of the constant “cutting down” and returning chips to the game, a “critical mass” of repetitive positions accumulates. ZoG counts out the third repetition and announces that the game has ended in a draw! I can say that it is very disappointing, having almost finished the game, on the last move, to find out that, in the opinion of the program, there was a draw. The saddest thing is that there is no way to cancel this check (which obviously does not make much sense in games with random generation). You can not even increase the value of the number of repetitions at which the game ends! This is exactly what I call the dark side of the ZRF .

I had to add variants of the game with a random opponent (since games for one player are treated as puzzles in ZoG, for obvious reasons, control of repetition of positions is turned off), while refusing to use the very convenient predicate friend? (it suddenly turned out that the random had no friends). In the end, all the problems with the implementation was solved by bringing the game back to life, which may have been played 5,000 years ago.

We have forgotten a lot ...
But we remember the lost ...
Or create something new.