Igomokunarabe


#1

I thought of a silly game, combining (i)go and gomoku(narabe).

For those that are not familiar, gomokunarabe (meaning line up 5 stones) is a game that is played on a goban, with go stones, alternating between the players, where the goal is to get 5 stones in a row (horizontally or diagonally). It’s like connect four five without gravity.

My game shall henceforth be known as igomokunarabe, also know as gomokunarabaduk in Korean (because why not create stupid puns for a stupid game). The rules are simple:

  • It’s just normal go, but each time you complete 5 stones in a row, you gain 10 points!

Gain 10x your normal score by crawling on the second line! Build a B2 Bomber that is an actual tactical bomber, especially if it’s floating in the middle of the board without any enemy stones around! Get crazy high scores by playing out ladders!


#2

For those that have difficulties with the foreign vocabulary, we could also just call it “five in a go”


#3

Are the points gained immediately, even if the stones eventually die?

Would six stones in a line count as a two five-in-a-rows? Would a five-by-five block count as 12*10 points?

It seems like it would be hard to count all of the possible five-in-a-rows. How many points are in a 6-by-6 block? There would be an entire end-game phase of filling in one’s own territory to make more five-in-a-rows.


#4

These are important questions to be asked, indeed.

How about you gain them immediately, but capturing 5 stones in a row is worth 20 points?

This is quite a fun combinatorial puzzle to solve. I made the following look-up table (values should be times 10):

Look up table

Oh my, there’s a whole world of tactics here, including trying an invasion not to live, but to make the last two eyes as inconveniently placed as possible!


What about this beautiful move, worth a difference of 100 (and 2 for the reduction in territory) points if white had played in between the black stones instead:


#5

Wow, takes combinatorial game theory to another level