Normal sudoku rules apply. Along a thermometer, digits must increase from the bulb end. Kings are 1, Rooks are 2, Bishops are 3, Knights are 4. No King can be “in check”. Ie No two Kings can be a “Kings Move” apart; no King can be a “Knight’s Move” from any Knight; no King can be on the same diagonal as a Bishop, unless a Knight, Rook, or Pawn is blocking the path; no King can be in the same row or column as a Rook unless a Knight, Bishop, or Pawn is blocking the path; pawns moving down the board are 5. No King can be on a diagonal in the row below a downward moving pawn. Pawns moving up the board are 6. No King can be on a diagonal in the row above an upward moving pawn.