How to checkmate with two bishops
Learn the king and two bishops checkmate move by move: put the bishops side by side as a wall, push the king to the edge, then into a corner, and avoid stalemate.
Build the wall
Two bishops side by side cover two neighbouring diagonals, and the king can't step across them. Build that wall in the centre, then bring your king behind it.
The bishops are strongest side by side in the centre. Start with Be3. Be3 Kd5
1… Kd5 The king stays in the centre and steps to d5.
Play Bd3: now the bishops stand side by side, and their diagonals make a wall. The king is locked in the shaded 20 squares. Bd3 Ke5
2… Ke5 It can't cross the wall, so it walks along it, back to e5.
The bishops can't hold the wall forever without help, so your king walks up. Play Ke2. Ke2 Kd6
3… Kd6 The king steps back to d6, the middle of its box.
Push the wall up: play Be4. The bishops on e3 and e4 still stand together, and the box shrinks to 16 squares. Be4 Ke5
4… Ke5 It comes straight back to e5 and attacks your bishop on e4.
Play Kd3: your king guards both bishops, and the wall holds. Kd3 Ke6
5… Ke6 Both bishops are guarded, so the king steps back to e6.
The bishops stand side by side, your king guards them, and the black king is shut in 16 squares at the top of the board. Next, push the wall to the edge.
Push the king to the edge
Step one bishop forward at a time so the two stay next to each other, and bring your king up behind them.
Push the wall up: play Bf4. The bishops still stand side by side, and the box shrinks to 12 squares. Bf4 Kf6
1… Kf6 The king walks along the wall to f6.
Bring your king up behind the wall: play Kd4. Kd4 Ke6
2… Ke6 It comes back to the middle, e6.
Play Be5: the wall moves up, your king guards both bishops, and only nine squares are left. Be5 Ke7
3… Ke7 The wall pushes it back to e7.
Play Bf5: the bishops stand side by side on e5 and f5, and the king has six squares by the back rank. Bf5 Ke8
4… Ke8 The king goes to the back rank, e8.
Play Bf6: now it has only four squares. Bf6 Kf7
5… Kf7 It comes out to f7 and attacks your bishop on f6.
Play Ke5: your king guards the bishop. Ke5 Ke8
6… Ke8 The bishop is guarded now, so the king goes back to e8.
Play Be6: now it can only walk between e8 and f8. Be6 Kf8
7… Kf8 f8 is its only move.
The black king is stuck on the back rank with two squares, e8 and f8, and the bishops hold it there by themselves. Now your king can walk over.
Into the corner, then mate
Walk your king over to the h8 corner, then drive the black king into it. On the edge, look for stalemate before every quiet move.
The bishops hold the box, so your king is free to walk. Play Kf5. Kf5 Ke8
1… Ke8 Back to e8: it has nothing else.
Play Kg6: your king takes f7, g7 and h7, the squares next to the h8 corner. Kg6 Kf8
2… Kf8 Back to f8.
Bf7 looks natural, but the king would have no move and no check: stalemate. Take e8 instead and send it towards the corner. Play Bd7. Bd7 Kg8
3… Kg8 The king has to go to g8.
Play Be7: it takes f8, and the king has only h8 left. Be7 Kh8
4… Kh8 Into the corner: h8 is its only square.
Be6 would take g8 without check: stalemate. Leave it g8 and make a waiting move. Play Be8. Be8 Kg8
5… Kg8 It comes out to g8, the square you left it.
Play Bf7+: it has to go back to h8. Bf7+ Kh8
6… Kh8 Back into the corner, its only move.
Your king covers g7 and h7, the bishop on f7 covers g8. Play Bf6: check along the long diagonal, and it's mate. Bf6#
Checkmate. Keep the bishops side by side as a wall, push it forward with your king guarding it, and in the corner leave the king a square until the check that mates.
Key ideas
- Side by side, two bishops cover two neighbouring diagonals: a wall the king cannot cross.
- Push the wall forward one bishop at a time, and keep the bishops next to each other.
- Your king walks up behind the wall and guards the bishops whenever the enemy king attacks one.
- Drive the king to the edge, then into a corner. A bishop check sends it the right way.
- Near the corner, leave the king a square until the mating move: most quiet moves there are stalemate.
Common mistakes
- Putting a bishop next to the enemy king where it can be taken, like Bf4+ Kxf4 in the first position.
- Leaving your king behind: when the enemy king attacks a bishop, nothing guards it.
- Stalemate in the corner: a quiet bishop move like Be6 with the king on h8 takes its last square without check.
- Chasing the king with checks instead of keeping the bishops next to each other.