There's one detail demanding attention: a pawn on the 9th rank, no piece being lost by its side - a legal possibility - cannot move. However, if it attacks the opponent's King, it nevertheless gives check.
(Note: this is similar to a pinned piece that nevertheless gives check).
no Sound  -  Flip board
Broken canvas...
to move
   
 
   
 

There's no better way to show that an option to promote is better than an obligation, than P. H. van den Muijzenberg's 'checkmate in 2'