WCCC 2018, the 24th World Computer Chess Championship, continued the ICGA's longitudinal computer chess experiment begun in 1974. This event was held in Stockholm, featured eight chess engines and was won by KOMODO after a play-off against GRIDGINKGO.

This paper considers the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>2</mml:mn> <mml:mo>×</mml:mo> <mml:mn>4</mml:mn> </mml:math> variation of a popular 2-player imperfect information game Chinese dark chess (CDC). The <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>2</mml:mn> <mml:mo>×</mml:mo> <mml:mn>4</mml:mn> </mml:math> version is solved by computing the game-theoretical value of each position for all possible material combinations with at most four red pieces and four black pieces. The experimental results show that where to make the first move, which must be a flip, is the most important factor to affect the outcome of a game. We find that choosing a square to flip that has the best-expected outcome may not be the best strategy. Instead, a square that has the best-expected difference before and after the first move is made should be chosen. We also discover that <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>2</mml:mn> <mml:mo>×</mml:mo> <mml:mn>4</mml:mn> </mml:math> CDC is unfair and it is favorable to the second player, but some openings are fair. We believe observations and techniques made here can be used to improve the performance of programs for playing the original <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>4</mml:mn> <mml:mo>×</mml:mo> <mml:mn>8</mml:mn> </mml:math> full version of CDC.

For the first issue of our 2018 volume of the ICGA journal, we are happy to return to our roots and bring you two articles on the latest research for the games chess and shogi.The first article, by John Fishburn, investigates the construction of a chess opening book based on computer search rather than historic game records.The work is interesting in that this automatic search-based approach can be tailor-made to play against a particular player or computer program, if a probabilistic model of the opponent's opening moves can be provided.The second article, by Takafumi Nakamichi and Takeshi Ito, describes a method of tweaking the playing strength of shogi programs so that they may fit the skill level of a human opponent, while simultaneously resembling the way a human plays so that more enjoyment can be achieved.In addition, we follow up the coverage for the 2017 events in Leiden in this issue, with the reports on the 7th World Chess Software Championship and the World Speed Computer Chess Championship in 2017.

Computational complexity of a computer game is an almost insurmountable obstacle in the process of looking for an ideal solution. Nevertheless researchers in the field of computer games aim to find such solutions, which may range from tractable to in