Chess-End Game

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K vs K+P

We call Bare King (BK) (also known as lone king) the king without any other piece on the board, and Attacking King (AK) the King with accompagnying pawn. For the sake of clarity we assume that AK is white and BK is black.

Square rule
  • If BK is not in square in front of white P, P can queen without assistance from attacking king.
Key squares

White wins if AK occupies a key square.

  • rook pawn - key squares are either b7+b8 for a-pawn and g7+g8 for h-pawn.
  • other pawn, on 2nd, 3rd or 4th rank - 3 key squares: d2 → c4+d4+e4, d3 → c5+d5+e5, d4 → c6+d6+e6.
  • other pawn, on 5th or 6th rank - 6 key squares: d5 → c6+d6+e6+c7+d7+e7, d6 → c7+d7+e7+c8+d8+e8.
  • other pawn, on 7th - 5 key squares: d7 → c7+e7+c8+d8+e8.

Only exception is the case of knight pawn with black in the corner, and Black is to move (7k/5K2/6P1/8/8/8/8/8), or same position with AK at f8. If Black is to move, position is stalemate. Otherwise White wins.

Opposition
  • When two kings are only separate by one square, the king that has the move loses the opposition, because he cannot prevent the opposing king to progress. We say that the other king has the opposition.
  • Opposition is only a means to an end. The objective is to penetrate a key square, and doing so must be prefered over having the opposition.
Rules for non-rook pawn
  • Rule 1: With one exception, if the black king can get to the square in front of the pawn or the square in front of that (which are key squares), he draws.
Only exception is the situation where BK is on 8th rank and AK is next to his pawn, and White is to move (3k4/8/3PK3/8/8/8/8/8). In that case, White wins by advancing his pawn. Otherwise, if Black is to move, black draw by moving in front of White king, prevent him to reach the key squares.
  • Rule 2: White wins if at least any two of the following conditions are met:
    1. White king is in front of the pawn.
    2. White king has the opposition.
    3. White king is on the 6th rank.
Remember however that first rule above gives a condition for Black to draw. Also, White always wins if his king occupies a key square (with an exception for the knight pawn).
Rule for rook pawn
  • BK in f7,f8,g6,g7,g8,h6,h7 or h8 (h-pawn)
In general, BK draws if he can reach these squares, whatever the side to move first. The exceptions are listed below.
  • P on 6th rank, BK in f8 — White wins if AK is in f6 or g6 with White to move. The winning move is h7.
  • P on 7th rank, BK in f7 or f8 — White to move wins easily because BK is not in pawn promoting square. Black to move draws by moving to the square diagonally adjacent to the promotion square.
  • BK in f6
In that case, BK cannot prevent AK to occupy the key square g8. But AK only wins in the following situations:
  • P on 5th, 6th or 7th rank, White to move,
  • P on 6th or 7th rank, Black to move.

Tips

  • White must always move pawn from 6th to 7th rank without check to BK!
This way BK cannot move to square in front of the pawn, blocking the pawn.

Pawn endings

Corresponding squares
  • See Chess King, Endgames (Android).
  • If one side has more escape square, this side wins by triangulation.
  • Ex: 2k5/8/p1P5/P2K5/8/8/8/8. When White moves to d6,c5,d5, Black replies with d8,c7,c8, but White has to escape square: c4,d4, whereas Black only has one:b8.
Outside passed pawn
  • An Outside passed pawn is the a passed pawn that is most remote from the center. Plan is to divert opponent's king by the advance of this pawn.
Shoulder charging
  • See Chess King, Endgames (Android).
  • Move towards the opposing King to slow down his progression.

Tips

  • In 8/6p1/6K1/7P/8/6k1/8/8, Black to move draws because he stays 1 square away from White King. So if White captures black pawns, Black may capture White pawn. However, White to move wins because Black king is 2 squares away.
  • In 8/6p1/8/6P1/8/4K3/8/5k2, White wins with Kf3, but only draws with g6. Even if Black has the opposition own the f column, White wins because he can reach squares e6 and f7 to capture black pawn. In the latter case, White can either not prevent Black to reach square h7, or must enter in opposition in square g5, which draws because square f6/h6 are not accessible to White King.

Rook & pawns

Objectives

K+R+1pawn vs. K+R

  • Get your rook behind the pawn to promote.
  • Try to get control of the promotion square with your king.
  • The best way to block a passed pawn is with the king. Even more, if the opponent king can reach the promotion square, the game is draw.

K+R+2pawn vs. K+R

  • Try to get control of the promotion square with your king.
  • If that's not possible, it means that opponent king will be blocking your pawn.
  • So use 1 pawn to immobilize the opponent king.
  • Push your other pawn. To stop this pawn, the opponent will have to use his rook, which will then be immobilized.
  • Use your other king so that to attack opponent rook, and get access to the promotion square of this other pawn. This require to a the right time to move your rook behind the pawn blocked by opponent rook.


Traps:

  • Don't let opponent check your king followed by capture of your rook.

Other information:

  • Square rule (telling whether a king alone can stop a passed pawn)
  • King is the best to stop a passed pawn.
  • Rook is very bad a stopping a passed pawn. If so, it is completely immobilized. The best way to attack such a rook is with the king.