A skewer is a tactic where a valuable piece is attacked and forced to move, exposing a less valuable piece behind it to capture. It is like a pin in reverse: the more important piece is in front instead of behind. For example, checking a king that stands on the same line as its rook forces the king to step aside, letting you take the rook. Only long-range pieces — bishops, rooks, and queens — can skewer, because they attack along lines. Watch for enemy kings and queens lined up with other pieces, since those are prime skewer targets.