(1) Stacking Cannons Checkmate
This is a checkmate that may occur early in the game, very often seen in games of children beginners. Two red Cannons are piling up directly in front of the black King. The real Cannon is serving the check with the front Cannon as its carriage.
In this situation, black can only answer by either getting his King out of attack, or plugging a piece if available, between the two offensive Cannons. He cannot simply move a piece to shield his King, as that piece will become a carriage for the front Cannon, and render his King in check. For this example, black cannot protect his King with either Adviser. The advisers are unable to come to the King’s rescue. Worse still, they are obstructing its escape route.
The two Cannons form the Attacking Force. But the front Cannon plays dual role here. Together with the two black Advisers, it forms the Intercepting Forces.
Here are two mating combinations leading to the Stacking Cannons checkmate. The first one in particular is very useful in real game.