Interference (chess) Interference (chess) In the game of chess, interference occurs when the line between an attacked piece and its defender is interrupted by sacrificially interposing a piece. It is a chess tactic which seldom arises, and is therefore often overlooked. Opportunities for interference are rare because the defended object must be more valuable than the sacrificed piece, and the interposition must itself represent a threat. In the position at left, White to play will apparently be obliged to retreat the knight from f5, because the squares to which it could advance are all guarded. However, the interference move 1.Nd6+ interrupts the
Fairy chess piece Thus, the ferz is now considered a non-standard chess piece. Chess enthusiasts still often like to try variations of the rules and in the way pieces move. Pieces which move differently from today's standard rules are called "variant" or "fairy" chess pieces. Fairy chess pieces usually fall into one of three classes, although some are hybrids. Compound pieces combine the movement powers of two or more different pieces. An ("m","n")-leaper is a piece that moves by a fixed type of vector between its starting and destination squares. One of the coordinates of the vector 'start square – arrival square' must