Waki System.

Static rook, the Yagura · castles into Yagura · 脇システム Waki shisutemu

The idea

The Waki System is Black’s answer to White’s usual move against the Yagura Silver-37, the bishop out to 6d.

Black brings the bishop from 7i to 4f, facing it, and both sides then castle into Yaguras that are nearly mirror images, with the bishops still facing each other: whoever trades them spends a move, so neither side hurries. ja.wikipedia says the shape is old, but that Waki Kenji studied it in great depth and played it often, which is how it got his name, and that some players have analysed its lines all the way to mate.

Black’s main plans are to trade and hand the move back, to push the edge pawn and the 3rd-file pawn, or, as here, to trade bishops and send the right silver up to 2f as a Climbing Silver. White answers with a bishop dropped on 6i, which the source calls a strong reply, and Black attacks the edge regardless.

The whole order has one source, which says the moves after the bishop drop follow professional games; ja.wikipedia’s basic position is the one at move 40.

How it goes together

Both sides’ moves are shown, because this opening is an agreement rather than a system: one player cannot reach it alone, so a one-sided list of moves would be a fiction.

The plan once you are set up

• Play the 24-move Yagura and the silver to 3g.
• When White’s bishop comes out to 6d, answer with the bishop to 4f.
• Castle the king on 8h; push the rook pawn to 2e and the edge pawns to 1f and 9f.
• Trade bishops on 6d and bring the silver to 2f.
• Against a bishop dropped on 6i, push the edge pawn to 1e and take back with the silver, then attack the edge with pawn and bishop drops.

What to watch for

• White trading bishops first. shogi-joutatsu says an immediate trade by White helps Black’s silver forward and leaves Black better.
• The bishop drop on 6i. After the trade it hits the gold on 7h and the pawn on 4g; in this line Black lets it promote on 4g and keeps attacking.
• On the edge, take with the silver. After the pawn to 1e and White’s capture, shogi-joutatsu stresses taking with the silver, not the lance.
• Deep theory. The system is known for long analysed lines, and Shogi Wars warns that one wrong move can lose at once.

What it is played against

White builds the same Yagura with the bishop on 6d and the silver on 7c. White can trade bishops early, keep waiting, or, after Black’s trade, drop the bishop on 6i and fight on the 4th file while Black attacks the edge.