p.boxed
  | Two new pieces: marshall and cardinal. Bigger board.
  | Orthodox rules with a few adaptations.

p.
  Grand chess is played on a 10x10 board.
  Two new pieces appear: the marshall and the cardinal, written respectively
  M and C. A marshall has the moving abilities of a knight + a rook, while the
  cardinal equals a knight + a bishop.

figure.diagram-container
  .diagram
    | fen:10/10/10/10/10/2R2Q4/10/4c5/10/10:
  figcaption The black cardinal can take on c5 and f5.

h3 Special moves

p Castling is not permitted.

p.
  Promotion is mandatory for a pawn reaching the last rank. However, they can
  only promote into a friendly piece captured (which is back on the board).
  If none is available, the promotion on last rank is impossible and the pawn
  cannot move (but still gives check).

p.
  Pawn promotion is possible (but not forced) on the two ranks before last,
  only in an already captured (friendly) piece.

h3 Source

p
  | Grand chess page on 
  a(href="https://www.chessvariants.com/large.dir/freeling.html")
    | chessvariants.com
  | .

p Inventor: Christian Freeling (1984)