The Protected Passed Pawn
White to play and win
PlayYour passed pawn is guarded by its neighbor, which makes it untouchable. The defending king is chained to it for the rest of the game, and a chained king cannot defend anything else.
No signup needed. The opponent never gives up, and every mistake gets explained.
The Protected Passed Pawn
Win against perfect defense
Waking the engine…
The theory
The outside passed pawn wins by decoying the defender away. Its cousin, the protected passed pawn, wins by something even stronger: it freezes the defending king in place for as long as you like.
Double immunity. A passed pawn defended by another pawn cannot be captured by the enemy king: the recapture square is covered, so the capture is simply illegal. And the king cannot walk away from it either, because the pawn would run. The defender is locked inside the pawn's square with no way to make progress and no way to leave. You, meanwhile, own the rest of the board.
The winning plan writes itself: leave the frozen duo alone, walk your king to whatever else the defender owns, and take it. Return with an extra pawn or an extra entry square, and zugzwang finishes the job. There is no counterplay: counterplay requires a defender who can move.
The one way to lose it is to release the tension. Pushing the protecting pawn feels active and throws the win away on the spot: the passer loses its guard, the enemy king takes it, and the game is drawn. In this drill that single pawn push is the difference between winning and shaking hands, and the tablebase will accept the handshake instantly.