Edge King Silver Crown.

How it goes together

Start from a Tenshukaku Mino: king 8g on the bishop’s head, silver 7h, golds 6i and 5h. The king steps diagonally back to 9h, above the lance. The silver climbs from 7h into the 8g square he has left and becomes the crown. The 6i gold comes up to 7h under the crown, and the 5h gold steps across to 6h beside it. The 7h gold now guards the crown, the bishop and the 6h gold; the 6h gold guards it back, and the right silver on 5g too.

An Edge King Silver Crown is a Tenshukaku Mino with four more moves: the first eleven below are that castle.

Move by move

Black only, from the start position. The first eleven moves are the Tenshukaku Mino; the last four are the king, the silver and the two golds, in the order the Japan Shogi Association’s column and shogi-gym both give.

Fifteen moves. The king has left the keep for the edge, and the square he stood on, 8g, now holds the silver crown. The JSA column points out that his first step up to 8g was not wasted: it is how he gets to 9h.

What it is good against

The head and the diagonal. On 9h the king is off the long diagonal that runs through the bishop on 8h, and Shogi Wars says the castle has a thick head and well-connected generals. The silver covers 9f, 8f and 7f in front, and the bishop guards 9g, the square over the king.

Where it breaks

The edge, the side and the bottom. The king stands on top of his own lance, so the lance cannot move, and ja.wikipedia says a castle with the king there is not especially strong from the side. On the bottom rank only the 6h gold guards 6i, and the 8f pawn in front of the crown is guarded by the silver alone.

When to build it

A static rook castle against a ranging rook, grown out of a Tenshukaku Mino: shogi-gym gives it as the way to rebuild when the king’s head comes under attack. For the four-general form with the king on the same square, see the Yonenaga King.