The opposition is lesson 1 of 6 in Endgame 2: King and pawn, an endgame course suited to players rated around 800 (beginners). Kings face to face with one square between them: whoever does not have to move holds the opposition, and the other king must give way. It has 7 interactive exercises: 7 calculated lines from real positions. You play every move on a board and get feedback straight away. The lesson is free.
What this lesson explains
Look at the two kings: they stand face to face on the d-file with one square between them (d4). A king may never step next to the other king, so neither can go to d4, c4 or e4. This standoff is called the opposition.
Now it is Black's turn. Black would like to stay put, but must move, and every king move gives way: after ...Ke6 the white king walks forward to c5. Whoever does NOT have to move holds the opposition. Here that is White.
How to take it: move your king so that the kings face each other with one square between them and it is the other side's turn. Here White plays Ke4: e5 is between the kings and Black must give way. In every exercise below your first move is such a king move; then walk your king forward and push the pawn.
What you practise
White to move: take the opposition with your king, then win. (4 positions)
Black to move: take the opposition with your king, then win. (3 positions)
Worked examples
White to move: take the opposition with your king, then win. 1.Kc5 Ka4 2.b6 Kb3 3.Kd4. Kc5 took the opposition: the defending king had to give way. This is a won endgame (checked with endgame tables). After Kd5 the win would be gone.
Black to move: take the opposition with your king, then win. 1...Kf4 2.Kg2 Kg4 3.Kh2 Kf3. Kf4 took the opposition: the defending king had to give way. This is a won endgame (checked with endgame tables). After Kd5 the win would be gone.
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