Shogi strategy
Shogi, like western chess, can be divided into the opening, middle game and endgame, each requiring a different strategy. The opening consists of arranging one's defenses and positioning for attack, the middle game consists of attempting to break through the opposing defenses while maintaining one's own, and the endgame starts when one side's defenses have been compromised. Tactics Many basic tactics (手筋 tesuji) of shogi are similar to those of chess tactics, involving forks, pins, removing the defender and other techniques, all of which are considered very strong when used effectively. However, other tactics, particularly ones involving dropped pieces, have no parallel in western chess. Relative piece value Shogi pieces may be considered to have different valuations in which some pieces are generally more valuable than others – all other things being equal. (Cf. piece value in western chess.) There are three main valuation groups: the king which has an absolute value since the game is lost if mated the two major (most mobile) ranging pieces (大駒 oogoma): rook, bishop the minor pieces (小駒 kogoma): pawn, lance, knight, silver, gold The minor pieces can be further grouped in the following valuation hierarchy: gold > silver > (knight, lance) > pawn Sometimes, the relative pieces are formalized with specific numerical values. This is particularly common in the explicit formalizations found in computer shogi. For instance, Reijer Grimbergen uses the following relative values in a Move Merit Analysis formalization: Grimbergen notes that, unlike western chess, shogi piece valuation is not standardized as different players disagree on the exact values. Another formalization used by program YSS 7.0 of 1997 had the following relative values: Kōji Tanigawa, Yasumitsu Satoh (佐藤康光), and Larry Kaufman suggest the following values: Under two of these valuation schemes, the promoted pawn, lance and knight all have a higher value than a gold even though when promoted they move the same as a gold. The reason for this is that they will return to their lesser values when captured by an opponent whereas a captured gold gives the opponent a relatively more valuable piece. Kaufman, for example, notes that exchanging a promoted pawn for a real gold is often a good material gain tactic because the player with the promoted pawn loses only two points while his opponent loses seven. Relative piece valuations are used to roughly evaluate piece exchanges. For example, if there is an opportunity to capture two golds from an opponent by giving up a rook and a pawn, using Kaufman's scheme, this is seem as a favorable trade (all else equal): (gold + gold) > (rook + pawn) (8 + 8) > (13 + 1) However, this wouldn't be a good trade if the rook was promoted: (gold + gold) < (dragon + pawn) (8 + 8) < (17 + 1) Castles In shogi, strong defensive fortifications protecting the king are known as castles. There are many types of castles and variations which can be used, but it is essential to understand which ones are useful