One of the tactical methods is space clearance. According to the book of IM Paul Littlewood, ” Chess tactics” it appears, when:
“Square or diagonal needs to be cleared of your own or opponent’s pieces, before a winning combination can occur on that square or diagonal.” You should imagine the position without the obstructing piece on the way.
I played a blitz game today and got a little example of it, Black to move:
The answer ( if necessary) is in the comment.
