Finally, some positions illustrating interactions between back rank patterns and the removal of the guard. In this first example you see your two rooks on open files and imagine each of them penetrating to Black’s back rank. Rd8 would mate with support from the bishop on a5, except that Black guards the mating square with his own bishop on f6. Rh8 also would mate—again, except for the f6 bishop. That train of thought naturally leads to the conclusion that Black’s bishop is overworked, and that playing both rook moves might succeed where neither would alone. Starting with Rd8+ fails because then Black’s bishop ends up on d8 and blocks the check from your rook on the h-file. But 1. Rh8+ forces BxR, and then leaves behind a loose square where Rd8# can be played.