It isn't always possible for the unmasking piece to deliver a check, nor is it always necessary; any move that creates two threats at once has winning potential. Here are some positions where the unmasking piece makes a capture or threat that serves the same distracting purpose as a check.
In this first position, White's bishop and rook on the c-file are in the characteristic formation for a discovery, with Black’s loose knight providing a suitable target. White just needs to vacate the bishop from the file forcefully. The types of moves considered in the previous section won’t work here because White has no checks. But he has another violent move at his disposal: BxN, taking a knight and threatening the rook on f7. Black’s king isn't threatened, but he nevertheless must redress his loss and protect his rook with KxB—after which White can play RxN, winning a piece.