Diagonal Oblong Chess
Chess variant played on a rectangular-like board with diagonal square grid. The roles of the orthogonal and the diagonal directions are exchanged.
Otherwise the rules of chess apply, with the following differences:
Pawn's movement and promotion fields
Before and after castling
The bishop's and the rook's role has been reversed: the bishops can move in parallel to the sides of the board (which are diagonals of the grid), and the rooks can move obliquely (which are orthogonal directions in the grid). It is however still true that the bishops remain on the same field colour, while rooks do not have this restriction.
Shi Ji, 2010[ChV.com] – the difference is that the original version included a rule named "guarding", which is not present on this page.