These pieces will automatically promote to piece number 7 when they
reach last rank. So in normal Chess, piece 7 should be programmed as Queen.
-Castling currently can be done only with a piece number 6 in the corner,
-so in normal Chess you should program piece 6 as Rook. Any royal piece
-can in principle castle. (Subject to the normal restrictions on castling,
-i.e. not passing through check etc.) If you don't want that, remove the
-castling moves from the King desription. If the castling initiator does
-not start in a central file, the results are currently undefined.\r
+Castling can be done only with the original corner piece as specified
+by line 2 and 3. Any royal piece can in principle castle. (Subject to
+the normal restrictions on castling, i.e. not passing through check etc.)
+If you don't want that, remove the castling moves from the King description.
+If the castling initiator does not start in a central file, the results are
+currently undefined.\r
Most variant definitions can be seen at the end of this file.
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