Mnemonic piece symbols for the large Shogi variants

The chosen system uses a square with a size of about 60% of the board square as the basic shape. Such a square would indicate a piece that can do a single step in each of the 8 directions, like the orthodox King. (Note, however, that the actual King is represented by such a square decorated with a cross, to indicate its royalty!) For every direction in which the piece does not move, a 'bite' is taken out of the piece, either in the center of an edge (for missing orthogonal steps) or at a corner (for missing diagonal steps). If there are no moves in a number of adjacent directions, the outline of the piece will follow that of a square of about 20% board-square size in its center. In all cases concave 90-degree angles will be rounded, but convex 90-degree angles will keep sharp corners. This 'pointy' look will make stepping pieces, such as the various flavors of generals, easily recognizable.

In directions where the piece can move further than just a single step, it will 'bulge out' from the basic square, to nearly the edge or corner of the board square. This automatically makes pieces with a longer range look bigger. But it also causes a large shape contrast, because now the convex part of the piece is rounded, while the concave indents have sharp corners. The pieces with longer range will have a 'flower' shape when they move far in many adjacent directions, and a wind-mill shape when moving in just a few directions.

In the very large variants moves further than a single step need not always be of unlimited range: it Tai Shogi, for instance, they can be limited to 2, 3 or 5 steps. All these moves will lead to a similar bulge on the piece symbol, and they have to be distinguished from decoration on the symbol. An infinite range is indicated by a radial line on the piece in the corresponding direction. The increased amount of detail on the piece in general makes it more conspicuous than an undecorated piece. A bulge without any decoration is therefore used to indicate the piece has a range of 2 in that direction.

For intermediate ranges (larger than two, but not infinite) there will be a dot or small cross in the bulge. For a range of 3 this will be plotted close to the bulge, for larger ranges more to the center (but still clearly in the applicable direction from it). Most of the time the pattern of intermediate-range and other moves should unambiguously identify the piece anyway, but the position of the dot marker gives you an extra clue. Pieces that have a range-two move with linear Lion power (i.e. ability to multi-capture) will have the bulge decorated with an 'eye'.

Some pieces jump over a distance of exactly two squares. This is indicated by a roundish detached patch as far away from the center of the piece as possible, looking a bit similar to the bulge that a sliding move of range 2 would have. For pieces that make jumps like an orthodox Chess Knight, these patches are drawn along the edge of the board square between the center and the corner.

In Shogi pieces promote, but once they are promoted, they cannot promote even further. Some pieces that are in the opening position and can promote can also occur as promoted version of another pieces, which thus can no longer promote. Therefore it is desirable to distinguish promotable and non-promotable versions of the same piece. In the mnemonic piece set this is done by plotting a dot in the center of pieces that can no longer promote, whenever it is necessary to make that distinction.