Openings · 九間飛車
Ninth File Rook.
Push the edge pawn, lift the lance and put the rook behind both on the ninth file, so the whole column points at the opponent’s edge.
The idea
The Ninth File Rook is a recent idea. It grew out of a study video on professional Nakamura Taichi’s YouTube channel in 2024, and Shogi Wars soon added it as a collection item, describing a low ranging rook that looks harmless but can explode into an attack.
The rook does not stop on any of the usual ranging files: Black closes the bishop’s diagonal with the pawn on 6f, moves the bishop to 7g so the rook can pass along the eighth rank, pushes the edge pawn to 9f, lifts the lance to 9g and puts the rook on 9h behind it.
The six moves here are a blog’s recipe for triggering the Shogi Wars item, not a teaching line, and no encyclopedia covers the opening yet, so treat it as an experiment. The name runs against the usual count.
The Fourth File Rook and the Third File Rook count the files from Black’s left, and by that count the rook on 9h would be on the first file; the rook on 1h, which players call the First File Rook, is the one that would be ninth.
How it goes together
Only Black’s moves are shown. This is a build order rather than a game: the opponent is left standing still, because a reply on every move would hide the shape instead of explaining it. Every move was still played through the engine, so the position is one the rules allow.
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 | Why |
|---|---|---|
| 1 | ▲７六歩 7g7f | Open the bishop’s diagonal. |
| 2 | ▲６六歩 6g6f | And close it again with the pawn on 6f. |
| 3 | ▲７七角 8h7g | The bishop steps to 7g, so the rook can pass along the eighth rank. |
| 4 | ▲９六歩 9g9f | The edge pawn to 9f. |
| 5 | ▲９七香 9i9g | The lance steps up to 9g. |
| 6 | ▲９八飛 2h9h | The rook goes all the way across, to 9h, behind the lance: the Ninth File Rook. |
The plan once you are set up
- Open the diagonal with 7f, close it with 6f, and move the bishop to 7g.
- Push the edge pawn to 9f and lift the lance to 9g.
- Swing the rook to 9h, behind the lance.
- Castle. One blog suggests the Gold Twins first, then a Mino, with the left silver kept in the castle.
- Break on the edge when the pieces behind it are ready.
What to watch for
- Where the opponent’s king goes. One blog finds the edge attack strongest in a Double Ranging Rook game, against an Anaguma or a Mino castled on that side.
- Thin theory. Beyond a video and two blogs, nothing has been written about it yet.
- The order above is a recipe for the Shogi Wars item. A second blog shows White’s version, with the rook on 1b and the bishop and a knight joining the edge attack.
What it is played against
No source describes a standard reply. One blog says it works best in a Double Ranging Rook game, against an Anaguma or a Mino castled on the same side as the 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.