Fetlar Hnefatafl

Tafl rules
crust
Posts: 127
Joined: Sat Mar 21, 2015 9:29 am

Re: Internationally agreed 11x11 tournament rules - poll

Post by crust » Fri Aug 19, 2011 11:10 pm

Hello fellow players. The idea for this thread, as suggested by Aage on the game page forum, is to gather opinions and ultimately vote on what the international tournament rules should be for the 11x11 board. We can set up another for 9x9 to keep things simple. I think we should start by using this thread to air opinions and experiences regarding what makes the most balanced and functional rule set for experienced players. So if you are new to this site, PLEASE try out the variations yourself first. Playing two games is not enough! After twenty years of playing I am still being surprised by new strategies. Many opinions one reads online about hnefetafl rule reconstruction get bogged down in archeological source arguments. Those arguments are important, but in short, the existing sources are too vague to be sure about the rule details, so unless a glacier melts to reveal a viking rule book, we are stuck with playing the game in its many reconstructed variants and using experience and discussion to decide what seems to work best as an enthralling and complex strategy game. Aage's site has given us that possibility, and it is a goldmine of data. This thread is of course open to thoughts on the original sources, but as the experts haven't come to a solid conclusion our focus should be on quality of reconstructed gameplay.

One might fairly ask, why choose one rule set for tournaments if we can't know for sure? Simply because this game is likely to remain a curiosity as long as we can't agree on the rules, much as football matches often descended into chaos prior to the founding of the football association http://en.wikipedia.org/wiki/The_Footba ... on#History

I look forward to the day we can all sit around a table (no doubt virtual) and draft the official international rules. But before that we need to vote between the variations, and before that, lets have some focused debate. Pole now added! I have included only the basic rule sets from the gaming page. All rule sets assume that all pieces can move any number of squares available to them (not one step at a time), that the throne is passable by all pieces but only the king can stop on it, that the corners are hostile to all pieces, that the king can participate in capture both as anvil and hammer, and that the throne is hostile to the king (e.g. 3 pieces can capture a king next to the throne.) We assume the starting position is with black forming a diamond. All these details will need to be confirmed through a second pole once we have a clear favorite from the basic rule sets

Kratzer
Posts: 25
Joined: Sat Oct 03, 2015 9:28 am

Re: Fetlar Hnefatafl

Post by Kratzer » Sat Aug 20, 2011 11:59 am

Hi Adam, here's a first contribution from me. I've analized 54 shetland-fetlar-games from Aage's Homepage (including the tournament games) to find out if this variant is well balanced.

Result: The shetland variant is indeed surprisingly well-balanced.
We've got 39% wins for black, 17% draws and 44% wins for white.
As we can see there is a slight advantage for white, but I think that a variable between 1% and 5% is quite normal, also considering that 54 games is not enough for a definitive conclusion.
There is still no winning "formula", even extraordinaryly competent players like Tim or Pedro lose sometimes with their "strong" color against average players with good ideas.
The amount of draws increased noticeably with the recent tournament games, this is a phenomenon we will find more often during "important" games : white will always try to keep a chance for draw, that is for an important half point. What I still don't like about white is that it may force a draw without black having a chance to avoid it. For sure it's rare that a player does that two times in tournament, but we should create a rule for or against it, somehow ... any ideas?

I'm afraid, I can't upload neither pdf nor docx files here, so if some of you are interested in a preview of my little analisis, I can send it to you per E-Mail.

Next step will be to proof if there are types of openings, as in chess, that are more likely to win, or rather which these are. But therefore I need more time and more games to be played! ;)

PS: If something can't be understood, just ask again. My English is not as good as it could be!

Adam
Posts: 117
Joined: Fri Mar 20, 2015 1:28 pm

Re: Internationally agreed 11x11 tournament rules - poll

Post by Adam » Sun Aug 21, 2011 12:45 am

Roderich wrote: There is still no winning "formula", even extraordinaryly competent players like Tim or Pedro lose sometimes with their "strong" color against average players with good ideas.
This hits the nail on the head for this rule set quest. In short, there shouldn't be a winning formula. If there is, then all we have is glorified naughts and crosses, which I believe is what happens on the 7x7 board. Keep up the good work Roderich and let us know what you turn up. : )

User avatar
Hagbard
Posts: 688
Joined: Sat Mar 14, 2015 6:07 pm
Location: Copenhagen
Contact:

Re: Internationally agreed 11x11 tournament rules - poll

Post by Hagbard » Sun Aug 21, 2011 2:04 am

Beadle wrote:

The win:4 Draw:1 Lose:0 system sounds good, but perhaps excessive.
Rather than a win counting for 4 points, I might set it at 3 points.
I might not have any direct experience, but the math makes more sense to me that way, at least. We still want the draw option to have some value.
Compared to the 2:1 ratio with the current system, the 3:1 system would make a draw 2/3 as beneficial as it is now. With the 4:1 system, a draw would be 1/2 as beneficial as it is now.
That's the math. Choosing between 2:1. 3:1. and 4:1 is all a matter of opinion though. Experienced players will have a better idea of how the balance should work than I do.

Kratzer
Posts: 25
Joined: Sat Oct 03, 2015 9:28 am

Re: Internationally agreed 11x11 tournament rules - poll

Post by Kratzer » Sun Aug 21, 2011 9:46 am

The idea of giving more points for a win is in my opinion the right way – it motivates the player to take a risk, which is very important, although as student of literature I can't know if Beadle's 3 or your 4 points are the better option. :? Anyway, you know then that you can't barely get a good position point-wise if you don't try to win. And I agree with you, Adam, I like the possibility to force a draw – it contributes a lot to the game's intensity.
I think that there's only one problem left: imagine one player who has won all games from a tournament so far and who for reasons of calculations doesn't need points, or rather needs exactly a half point to win the tournament. What will he probably do playing white? He will built a draw fort – "The Skulking King" –. This would bring him on position n. 1 and a very unsatisfied opponent who won't have had a chance. The question seems to be, if we accept that as a "natural" game mechanism (then the winner shouldn't be blamed nor the loser pitied), or if we try to somehow prohibit this.

In the attachment you can finally find the announced file that I spoke off. Those 54 fetlar matches are those that I've found in the games archives which I have access to. If you have more noticeable games that should be in that list (there should be a lot since I took a long break from tafl in between), especially the ones between our advanced players, you can give the dates to me in the format of my file. This file is the base of my upcoming "researches" and will be updated regularly. Any suggestions for improvement of my overview are welcome!

EDIT: One more thing. I don't know if this is the right place to discuss that, but I really would like to know which are the established opening names and their exact coordinates – whatever starting position – so far (the Millar Gambit does already "exist", doesn't it?). This would make it easier talking about strategy in the future.

User avatar
Hagbard
Posts: 688
Joined: Sat Mar 14, 2015 6:07 pm
Location: Copenhagen
Contact:

Re: Fetlar Hnefatafl

Post by Hagbard » Mon Aug 22, 2011 9:12 am

Adam wrote:there is the potential in a tournament for white to refuse to enter into battle at all with the pictured monstrosity I like to call 'The Skulking King'.
What about
white wins: 1-0
black wins: 0-1
draw: 0-0

If the weakest player in a ten player tournament decides to cheat, using "The skulking King", he'll have 9 draws as white and 9 defeats as black.
This would with the 1/2-1/2 point system give him a score of 4.5 points.
But with a 0-0 point system this strategy would give him 0 points.

With a 0-0 point system, the only way to better your score position is to win. The reward for going for a draw when everything else fails, is that you prevent your opponent from earning one point as well.
Last edited by Hagbard on Tue Mar 17, 2015 7:30 pm, edited 2 times in total.

crust
Posts: 127
Joined: Sat Mar 21, 2015 9:29 am

Re: Internationally agreed 11x11 tournament rules - poll

Post by crust » Tue Aug 23, 2011 12:12 am

Hagbard wrote:What about
white wins: 1-0
black wins: 0-1
draw: 0-0
Hagbard wrote:With a 0-0 point system, the only way to better your score position is to win. The reward for going for a draw when everything else fails, is that you prevent your opponent from earning one point as well.
Bloody hell. Now, that's what I call thinking. How come I never have thoughts like that? I think my brain must be TOO highly trained.... I suggest we run the next 11x11 tournament under this 1/0/0 points system and see if we get fewer draws! Doesn't really affect 9x9 hnefatafl, as draws are pretty rare there (if not non-existent?). All hail to the mighty brain of Hagbard.

crust

User avatar
Hagbard
Posts: 688
Joined: Sat Mar 14, 2015 6:07 pm
Location: Copenhagen
Contact:

Re: Internationally agreed 11x11 tournament rules - poll

Post by Hagbard » Wed Aug 24, 2011 5:18 pm

Some considerations in support of details in the Fetlar rules as tournament rules:

Board size 11x11.
An analysis of the latest ten games on the 9x9 board between experienced players (king wins on board edge) gives on the average 31 moves and an average game length 23 minutes (6 white wins, 4 black wins).
The three longest games were 59 moves 38 minutes, 41 moves 35 minutes, 39 moves 28 minutes.

An analysis of twelve games from the recent tournament on the 11x11 board between experienced players (Fetlar rules) gives on the average 57 moves and an average game length 39 minutes (6 white wins, 4 black wins, 2 draws).
The three longest games were 83 moves 83 minutes, 143 moves 67 minutes, 80 moves 67 minutes.

As the figures show, the 9x9 game is rather short, about half an hour, while the 11x11 game can take up to slightly more than an hour.
Furthermore the 9x9 game lacks important phases which the 11x11 has, fx. there's not enough space to rescue the king with a draw. Also no specific corner fight, as the balance requires the king to be captured from 2 sides and win on the board edge.
So the 11x11 board is preferable over the 9x9.
Larger boards, 13x13 and 19x19, would much increase the game length for no reason, as the 11x11 game already has a suitable length and a varied game play.

Initial ordering white diamond, blacks in line.
On the 11x11 board, white can initially be placed in diamond or cross shape. When the white position is seen as a castle about to be attacked, the diamond shape is natural like the shape of a castle. That the center square is known as "the throne" also indicates the middle of the board as a castle.
A cross shape would picture the white team already scattered in the battle field, no castle.

Black can initially be placed in a 1-5 formation (a line of five with a group leader), or in a 1-2-3 formation. The latter places the front attacker right next to and in direct contact with the castle, would be an unnatural and unsafe position to await a battle, exposed beforehand to heavy rocks, boiling water etc.

The initial ordering used in the Fetlar game shows a natural picture of white team gathered in a castle around their king, and black team surrounding the castle in safe distance. The picture is silence before the storm.

Black begins.
The defenders await in their besieged castle, prepared for a hot reception of the attackers. It's natural that the attackers make the first move.

Pieces move freely like a chess rook.
Neil's research paper elaborates on this being as natural to vikings as a longship rushing from Norway to England in one swift move.

King is armed.
Neil's research paper also elaborates on the iron age / viking culture demanding the king to be as good a warrior as any of his men.

Capture against king's squares.
Neil's research paper again: this is necessary to prevent blocking of all corners by only eight attackers. That the king's squares are hostile to both white and black is an important feature for the corner fights!

No capture of whites against throne when occupied by the king.
If whites are captured against the throne even when occupied by the king, it is tedious to expand the white position without being captured. In that case, first the e6, f5, g6 and f7 have to moved into safety, before d6, f4, h6 and f8 can be moved.

King captured from 4 sides.
When the king is captured from 4 sides, the balance requires that he must go all the way to a corner to win. This gives a suitable length of fighting, plus the interesting phase of the corner fight.
If the king were to be captured from 2 sides, the balance would require him to win already on the board edge - thus missing the corner fights which add much to the game.

King not captured on board edge.
Against opponents like fx. crust and Adam, it turns out to be next to impossible to win as white without this rule. So the rule is necessary in high level games like a tournament.


The custodian capture and the defenders 1 : attackers 2 force I don't comment, since this is generally agreed upon. Neil's research paper comments on these aspects.


UPDATE September 5th
Now, if such considerations, even if based on available archeological and historical sources plus logics, known culture and common sense, were to result in an unbalanced game in practice, then some modifications of elements of the rules set would have to be found to move the balance.

Fortunately "the Fetlar rules set" has turned out to be quite balanced. Latest demonstration of this was the "unofficial tournament" on this site July 26th - August 15th 2011, with 6 white wins, 4 black wins and 2 draws.

Adam
Posts: 117
Joined: Fri Mar 20, 2015 1:28 pm

Re: Internationally agreed 11x11 tournament rules - poll

Post by Adam » Thu Aug 25, 2011 9:34 pm

Hagbard wrote: Initial ordering white diamond, blacks in line.
The initial ordering used in the Fetlar game shows a natural picture of white team gathered in a castle around their king, and black team surrounding the castle in safe distance. The picture is silence before the storm.
Some very convincing reasoning from Hagbard. Regarding the initial ordering, I would add that any opening position giving either white or black sole presence on the 3rd ranks and files gives a very strong, dare I say absurd opening advantage to that side.

Using allegory, an argument could be made for white opening as a sally forth from a besieged castle, though its a pretty thin argument. My feeling is that black opening is the right opening based on our tournament scores being so even.

User avatar
Hagbard
Posts: 688
Joined: Sat Mar 14, 2015 6:07 pm
Location: Copenhagen
Contact:

Fetlar Hnefatafl

Post by Hagbard » Mon Sep 19, 2011 8:23 am

May 11th 2010 crust emailed me an explanation of the draw concept in the Hnefatafl Fetlar rules, which I'd like to share on the forum:
... white may as well try to break out and seize control of a corner, and then go for a draw if that fails, and black manages to complete the encirclement. The interesting part comes when black realises that white has started to do this, and must work out how to stop it - often black will have to risk exposing a corner in order to prevent white from achieving the draw position. If that happens, white may have another chance at a win. So white is using the threat of a draw to disturb black's position, and thus create chances for a win. ... I don't see anything wrong in using the threat of a draw in the mid-game to get some leverage over black, especially after black has completed the encirclement - I mean, what else is there for white to do, apart from waiting to die?

Post Reply