Openings · 藤井システム
Fujii System.
Set up a Fourth File Rook and attack with the king still on its starting square, before the opponent can finish digging.
The idea
Every beginner is told never to leave the king on its starting square, and this opening does exactly that, on purpose. Fujii Takeshi built it in the 1990s to answer the Static Rook Anaguma, and the argument is arithmetic: burying a king in the corner takes ten moves or so, so if you spend those moves attacking instead, you get there first.
The first five moves are a Fourth File Rook, and then the king simply does not move. The edge pawn is pushed all the way through as a question, the knight comes to 3g, and the last pawn move prepares the one it is all for. If the opponent castles normally instead of digging, the king walks into a Mino after all and nothing has been lost.
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 | |
| 2 | ▲６六歩 6g6f | |
| 3 | ▲６八飛 2h6h | A Fourth File Rook so far, move for move. |
| 4 | ▲７八銀 7i7h | |
| 5 | ▲６七銀 7h6g | The silver, as usual. |
| 6 | ▲１六歩 1g1f | And here it stops being a Fourth File Rook: the king does not move. |
| 7 | ▲１五歩 1f1e | The edge pawn goes all the way through. Answering it on the edge costs the opponent a move they wanted to spend digging. |
| 8 | ▲３六歩 3g3f | Room for the knight. |
| 9 | ▲３七桂 2i3g | The knight to 3g, where it attacks 4e and 2e. |
| 10 | ▲４六歩 4g4f | And the move it is all for: 4e next, with the king still at home. |
The plan once you are set up
- The attack is the whole plan. The pawn to 4e, the knight into the gap, the edge already through: if it stalls, you are a king in the centre with nothing to show for it.
- Read the opponent first. This is an answer to an Anaguma, and against someone who castles quickly and normally it is simply worse than castling yourself.
- If the game turns slow, castle after all. The king can still walk to 4h and 3h into a Mino, which is why the silver and the gold are left where they are.
- Count their moves, not yours. The opening is a bet that they need ten moves to be safe and you need seven to be dangerous.
What to watch for
- Your own king. It is on 5i with the centre closed only by pawns, and one exchange in the middle can end the game.
- A bishop trade. With no castle, a bishop in hand aimed at your own camp is worse for you than for them.
- The opponent who does not dig. Against a boat castle and a quick attack, a king left at home is just a mistake with a name.
What it is played against
The Static Rook Anaguma above all: this opening exists because of it. Against anything else, castle.
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.