Showing posts with label Y. Show all posts
Showing posts with label Y. Show all posts

Thursday, May 03, 2007

Thoughts on Hex and Y

Scrabblette and I played a few games of Hex and Y last night. This was Scrabblette's first time playing and she didn't really get the strategy. (BTW, she subsequently beat me at Bridg-It, but this post is not about that.) After the game (and for a while when I would have preferred to be asleep) I was thinking about strategy for connection games on the hex grid. This post IS about that.

The basic tactic I understand involves the colours on the board above. If I've claimed two "adjacent" red hexes (or yellow, or white) and my opponent has not played on any of the spaces between them, I have an unbreakable connection between them. Hence for several games last night I was playing almost solely on the (let's say) red hexes until Scrabblette realised she'd lost.

Now where we're up to in our understanding of strategy is that the game is won or lost according to who claims the best chain of red hexes. But it occurs to me that the red hexes themselves form a hex grid, and you can make connections on that grid by claiming the blue hexes in this diagram:

And of course the blue hexes form a hex grid... and so on until we can identify exactly the most important hex that the opponent must claim in response to a move - the most important move at the highest level of abstraction. I know, I'm losing people here. Consider this colouring:

Say I'm trying to make a chain from top-left to bottom-right and I make my first move at A. (We're not using a pie rule here, we're not smart enough.) I'd love to make my next move at B, C or D so you should play there instead to prevent me. In fact if you let me play at A, B and D I believe the game is lost for you. So you play at C, I play at D and you play at B. It looks like if I play at B1 you'll have a really hard time getting through. Hmm... what happens next? I haven't figured that out yet.

Saturday, April 14, 2007

Y and Caeth Y

The game of Y is not on boardgamegeek as far as I can tell, so I'll tell you the rules. (Oops, yes it is.)
It's played on a triangular hex board. Each player has markers of a different colour and takes turns placing a marker on an unoccupied hex on the board. The goal is to connect all three sides of the board with a chain of your pieces. Corners count as being on both sides. That's all the rules there are, and the beauty of it is that one player must win.

Caeth Y is the same game using the caeth meta-rule. In a caeth game, rather than claiming cells you claim edges between cells. When you've claimed at least half of the edges incident with a cell, you claim the cell.
On this board, then, take turns colouring edges. If you've claimed half the edges going into a circle, colour the circle as well. When you've got a Y of circles connecting all three edges, you win. Note that the connectivity of your coloured edges is completely unrelated to whether you win the game or not!

I haven't played any of these games yet (I didn't have a board till just now!) but it seems to me that a small board would make the game too easy? So I've made some larger ones as well. Awfully smart people probably know how to force a win going first anyway, but I'm not awfully smart ye