Openings · 初手▲７八飛戦法
First Move Rook-78.
Swing the rook to the third file on move one, walk the king toward the corner, and only then open the bishop’s diagonal.
The idea
In a normal Third File Rook that keeps the bishop’s diagonal open, 7f, 3d and the rook to 7h run into the bishop trade on 8h and a White bishop dropped on 4e, and the sources treat that as too strong. This opening changes the order. The rook goes to 7h on the very first move, and the diagonal stays closed until the king has moved.
Against White’s 3d the king goes to 4h and then 3h. With the king on 3h covering 2g, the bishop drop on 4e no longer works, and the pawn to 7f can follow. Black gets a Third File Rook with the diagonal open, and can head for Masuda’s Ishida without losing a move. English sources write it 1. R-78.
It is also called the Cat Trick (猫だまし), after the sumo move where a wrestler claps his hands in front of the opponent’s face, because the big pieces meet on move one. White’s version, with the rook going to 3b on move two, is the Second Move Rook-32.
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.
Step through the moves, or press play.
Tap a move to jump to it. Arrow keys work once the board has focus.
Every move of the line, with reasons
| # | Black | White | Why |
|---|---|---|---|
| 1 | ▲７八飛 2h7h | △３四歩 3c3d | The rook to 7h on the first move, with the bishop’s diagonal still closed. White opens its diagonal. |
| 3 | ▲４八玉 5i4h | △８四歩 8c8d | The king first. Opening the diagonal now would allow the bishop trade and a bishop dropped on 4e. White pushes the rook pawn. |
| 5 | ▲３八玉 4h3h | △８五歩 8d8e | The king to 3h, where it covers 2g. White pushes on to 8e. |
| 7 | ▲７六歩 7g7f | △６二銀 7a6b | Now the diagonal opens: with the king covering 2g, the drop on 4e no longer works. White’s silver to 6b. |
| 9 | ▲７五歩 7f7e | The pawn to 7e, heading for the Ishida. |
The plan once you are set up
- Play the rook to 7h first and keep the bishop’s diagonal closed for now.
- If White opens its diagonal with 3d, move the king to 4h and then 3h before you push 7f.
- Open the diagonal with 7f once the king covers 2g. Against White’s rook pawn on 8e, the sources say the eighth file holds.
- Push 7e for an Ishida, or keep the rook on 7h, and finish the castle with the king on 2h and the silver on 3h.
What to watch for
- White’s rook pawn on move two. Then 7f has to come at once to cover the eighth file. A slower move such as the edge pawn leaves Black stuck, with White aiming at the edge.
- White exchanging rook pawns after your 7f. Take with the pawn, and after the rook takes back, trade bishops on 2b. Then play the rook to 8h, meeting White’s rook on the same file, or the bishop drop on 7g.
- White ranging its own rook. The game becomes a Double Ranging Rook, and the sources show Black fighting there with the diagonal still open.
What it is played against
White chooses. The rook pawn on move two leads back to familiar lines, and one of them, the bishop to 7g with the knight recapturing there, turns into the 新鬼殺し, a newer cousin of the Demon Killer. 3d followed by the rook pawn is the line above.
White can also range its own rook for a Double Ranging Rook.
Play it against the bot.
The bot’s search levels, 9 to 12, open from a book that holds two of these openings, the Fourth File Rook and the Yagura; the Mino levels play the openings people play. Either way the review afterwards shows you where the game left the line. Try the line, then try the plan.