Both bishops sweep the king down crossing diagonals
Both bishops work together: one delivers the check, the other defends and threatens. The shape often arises after a sacrifice that draws a defender onto a square the second bishop can take. Sibling of Boden's mate, but here the two bishops act on the same colour complex with one defending the other rather than crossing at right angles.
Both bishops survive into the attack, one delivers, one defends.
2 more clean runs (at any point) to reach Recall.
White to move. Black king on d8. Two white bishops on b5 and c3, both unobstructed and aimed at the queenside.
Both bishops survive into the attack, one delivers, one defends.
2 more clean runs (at any point) to reach Recall.