This RookUnderpromotion.cql finds Rookending studies wherein a pawn promotes to Knight, Bishop or Rook.
Created by Peter Boll.
(match
:pgn heijden.pgn
:output RookUnderpromotion.pgn
(position
:flipcolor
:variations
:promote [NnBbRr]
:piececount [QqNnBb] 0
:piececount R 1 8
:piececount r 1 8)
)
250 studies are found. Here a few presented: