p.
Two boards are used in this variant (represented on only one).
- Upside-down pieces appear at every "normal" pieces moves: they live on
+ Colored pieces appear at every "normal" pieces moves
+ (yellow for white, red for black): they live on
another board. When moved, they return to the initial board.
Orthodox rules apply on each board.
In addition, the final square should not be occupied by a piece from the
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+
+p Inventor: Vernon R. Parton (1953)