Smothered mate is a less common type of checkmate performed by a knight. A smothered mate occurs when a king is checked by a knight, but cannot move because he is completely surrounded ("smothered") by his own pieces. It usually happens in the corner, because it takes fewer pieces to 'smother' the king there. A typical example is shown below:
A wall of pieces surrounding the king is a good defence against most attackers, but not the knight, so watch out for enemy knights when your king has no squares to go to. Another time to be careful is at the beginning of the game - after all, the king starts the game surrounded by other pieces. Here is an example that has occurred many times over the years:
In general, it isn't too hard to defend against a smothered mate - just keep an eye out for enemy knights and give your king an escape square if there are too many pieces crowded around. Usually, it takes some effort on the attacker's part to lure the defending pieces into positions where they smother their own king. The most common sequence leading to smothered mate - which is worth the effort of memorising - is known as Philidor's legacy, after the 18th century player (and composer) François-André Danican Philidor.
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