From: Colin Paul Adams <colin <at> COLINA <dot> DEMON <dot> CO <dot> UK>
Date: 6 feb 2000
Subject: Chu Shogi castles (part II)

The simplest castle seen in Chu Shogi games (and by the castle, I mean
the pieces surrounding the King for defensive purposes IN THE ENDGAME,
or the late middle game - in the opening, it is irrelevant, and
checking opportunities do not tend to occur until towards the end of
the middle game), I call the Double Blind castle - for one obvious
reason, and because you have to be strategically short-sighted to use
it :-). It consists of the Drunk Elephant, placed on the square in
front of the King, and a Blind Tiger on each side square adjacent to
the DE.

This castle is WEAK. Firstly, it provides no protection against checks
on the back rank (these need to be covered in the endgame, or the
tactics will fail to work for you).

Secondly, the defence of the front of the King is extremely flimsy. In
the following position, Black has a choice of two different mates-in-one:

/6,K,5/
5,BT,DE,BT,4/
12/12/
5,ln,6/
12/12/12/12/
6,r,5/
12/12/

Even assuming that there is a side mover on the 'c' rank, Black should
be able to find a move from somewhere to give a threatmate.

This is the sort of position where you might be tempted to move the
King - in this case, a5 looks to be the square, as it is further from
the Lion. Now you count - how many moves will it take Black to bring a
diagonally moving piece to the 12h/7c diagonal?

If you have kept the Golds back, then this castle can be strengthened
at the front by moving the Golds diagonally forward, into the Ribbon
Castle:

/6,K,5/
4,G,BT,DE,BT,G,3/
12/12/
5,ln,6/
12/12/12/12/
6,r,5/
12/12/

Now all the frontal threats have disappeared (Black needs two more
ranging pieces, one to attack the Gold, and one to pin the Blind Tiger
which defends it), in order to threaten mate on just one square. This
seems to me good value for keeping back two Golds.

Also, White has more cover if he decides to run with the King. But the
Ribbon Castle is still weak against the checks on the back rank, so it
is not really satisfactory.
--
Colin Paul Adams
Preston Lancashire