Training notebook · Endgames
King and pawn opposition: decide who must give way
Opposition is a way to win access for your king, not a position to collect. Learn when facing the other king helps and when a pawn move changes the answer.
Start with the destination
Opposition describes a relationship between kings: in its simplest form they face one another on the same file or rank with one intervening square. The player who must move cannot approach directly. That can force a concession, but the useful question is which entry square becomes available afterward.
In a king-and-pawn ending, identify the squares your king needs to escort the pawn before choosing a move. Taking opposition while moving away from those squares can achieve nothing. A rook pawn near its promotion corner is an important warning: the defender may retain a drawing refuge even when the attacking king looks dominant.
Separate king moves from pawn reserves
A pawn move can transfer the obligation to move without changing the kings' relationship. That is why counting only king steps is unreliable. Before using a reserve pawn move, check whether the pawn remains protected and whether its advance removes a square the king needed.
Run the calculation in both directions. Ask what happens if the defender steps left and then if the defender steps right. If your plan only works against one voluntary retreat, you have not established the opposition's practical value. The opponent chooses the least helpful legal reply.
A two-turn study session
Open an opposition exercise from a reliable practice collection. Before moving, write the side to move, the pawn's file and rank, and two candidate king destinations. Predict which legal reply denies entry. Play the position once, then restart with the other colour and defend the same critical squares.
Afterward, change only the side to move using a study board that supports legal setup. Do not assume the result changes automatically; test whether a spare pawn move restores the original relationship. This controlled comparison teaches tempo more clearly than memorising a winning route.
Self-check: describe the concession
You understand the exercise when you can explain the square the defender abandoned and why the attacking king can use it. Saying 'I took opposition' is incomplete. Record whether the king entered ahead of the pawn, beside it, or not at all, and identify the first irreversible pawn move.
On a later attempt, stop before the critical decision and make the prediction again without replaying the solution. If you still choose correctly after the board is reflected, you are recognising the geometry. If not, return to the entry squares rather than repeating the same move sequence faster.
Distinguish the opponent's forced retreat from a voluntary one. During review, temporarily ignore the move actually played and find the most stubborn legal reply. A plan that still reaches its intended entry square against that reply is much stronger evidence of understanding than an easy conversion against an obliging defence.
Put the practice into a routine
Where Brass Pawn fits
Brass Pawn includes king-and-pawn drills with opposition themes. Use their feedback to test decisions against an engine; the app's 15-drill collection does not cover every possible opposition position.