chess tactic#2:skewer

In chess, a skewer is an attack upon two pieces in a line and is similar to a pin. A skewer is sometimes described as a "reverse pin"; the difference is that in a skewer, the more valuable piece is in front of the piece of lesser value. The opponent is compelled to move the more valuable piece to avoid its capture, thereby exposing the less valuable piece which can then be captured . The long-range pieces (queen, rook, and bishop) can skewer.
Skewers can be broken down into two types: absolute and relative. In an absolute skewer, the king is in check, therefore the check must be handled (under the rules of chess), whereas in a relative skewer, the pieces involved don't necessarily need to be addressed.