From: Manabu Terao <Manabu.Terao <at> JAPAN <dot> SUN <dot> COM>
Date: 23 apr 1999
Subject: Shogi strength drill - #25

Dear Shogi Fans,

Here is Problem #25.

Manabu Terao(on behalf of ISPS)


Problem #25

We often attack at the ear of the opponent's Rook on the
diagonal line of our Bishop. This is one of the examples. How
will you do that?

   9    8    7    6    5    4    3    2    1
+--------------------------------------------+       White in hand:
| wL | wN |    |    |    |    |    |    |    |  a   +------------------+
+--------------------------------------------+      |                  |
|    | wR |    |    | wG |    |    |    |    |  b   |                  |
+--------------------------------------------+      +------------------+
|    |    | wS | wP |    | wP |    |    |    |  c
+--------------------------------------------|
|    |    |    |    | wP |    |    |    |    |  d
+--------------------------------------------+
| wP | wP | wP |    |    |    |    |    |    |  e
+--------------------------------------------+
|    |    |    | bP | bP | bB |    |    |    |  f
+--------------------------------------------+
| bP | bP | bS | bG |    | bP |    |    |    |  g
+--------------------------------------------+      Black in hand:
|    | bK | bG |    |    |    |    |    |    |  h   +------------------+
+--------------------------------------------+      | P                |
| bL | bN |    |    |    |    |    |    |    |  i   |                  |
+--------------------------------------------+      +------------------+

Answer #25

   9    8    7    6    5    4    3    2    1
+--------------------------------------------+       White in hand:
| wL | wN |    |    |    |    |    |    |    |  a   +------------------+
+--------------------------------------------+      |                  |
|    | wR |    |    | wG |    |    |    |    |  b   |                  |
+--------------------------------------------+      +------------------+
|    |    |    | wP |    | wP |    |    |    |  c
+--------------------------------------------|
|    |    | bP | wS | wP |    |    |    |    |  d
+--------------------------------------------+
| wP | wP | wP | bP |    |    |    |    |    |  e
+--------------------------------------------+
|    |    |    |    | bP | bB |    |    |    |  f
+--------------------------------------------+
| bP | bP | bS | bG |    | bP |    |    |    |  g
+--------------------------------------------+      Black in hand:
|    | bK | bG |    |    |    |    |    |    |  h   +------------------+
+--------------------------------------------+      |                  |
| bL | bN |    |    |    |    |    |    |    |  i   |                  |
+--------------------------------------------+      +------------------+

The answer is : P*7d, S6d, P6e

Point : Aim at the "kobin"(ear) of the opponent's Rook

How about Bx7c+, Nx7c, P*7d? It is a strong attack by exchanging the
Bishop for the Silver and drop a Pawn at the head of the kNihght.
However, there will be not so effective move if White floats its Rook
to 8c.

P*7d, dropping a Pawn at the head of the Silver, is a good move in
this case. If White respond it by Sx7d, you will be able to capture
the Rook by Bx8b+ for almost nothing. if White neglect the P*7d,
the position will get worse by Black's Px7c+. Therefore, White's
response of S6d is compulsory but another natural attack to the Silver
by P6e  is a witty move. If White respond it by Sx6e, you will get
White's rook for almost nothing. If white ignore the P6e, your Px6d
will be a material-gaining move to enpower your Bishop. This type of
attack on the opponent's Rook by your Bishop often appears in Shogi.

"kobin" is a technical term to indicate the ears of a Rook or
a King which are usually vulnerable.