Mino castle

The Mino castle (美濃囲い minō gakoi or 本美濃囲い hon minō gakoi) is a castle used in shogi.

Mino castle is a defensive position that is considered easier for beginners, but still popular with professionals. (Mino is a historical province of Japan.) The King is placed in a safe position, while the three generals work well to back each other up. This is often used when a player chooses a Ranging Rook opening rather than a Static Rook opening.

The Mino castle takes five steps to complete, not necessarily in this order:

In modern shogi against a Static Rook position, the preferred order (as in the Fuji System) is to push the edge pawn and build the castle first, before moving the king. If the Static Rook opponent considers Anaguma, then a Ranging Rook player has the option of making a rapid attack, while leaving the king on its initial square. If Static Rook chooses a rapid attack himself, then Ranging Rook will start moving the king into the castle.

Another common variant also advances the fourth file pawn to 4f. This move reinforces the king's temple, the 3g square, from a bishop attack or defends from a knight being positioned on 5e also attacking the king's temple. It additionally makes way for a gold to advance to 4g in the development of a High Mino castle.

It is possible that a Mino castle can transition into a Right Yagura castle.

Incomplete Mino or Half Mino (片美濃 kata Minō) is a Mino with the leftmost gold is missing.

This is commonly seen as a transitional state when building a regular Mino since the leftmost gold is usually the last piece to move in the formation sequence.

However, an Incomplete Mino is also built for strategies (such as Opposing Rook) that use the gold on the other side of the board (where the rook is positioned). Also in Central Rook when the gold cannot move to the position that the rook is on.

The High Mino (高美濃 taka Minō) castle is a natural development from Mino castle when wanting to put pressure on a Static Rook opponent's castle or when being attacked from above as in a Double Ranging Rook game. Compared to Mino, it allows the player a greater potential for offense on the right side of the board and is stronger at the top although somewhat weaker from the side.

It is created from Mino, by pushing the 4th file pawn up to 4f (if it hasn't already) to make way for the gold that moves from 5h. This strengthens the castle against attacks from the front and allows further piece development.

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