Nightrider (chess) Nightrider (chess) A nightrider (also known as a knightmare or unicorn, though the latter sometimes also means the bishop+nightrider compound) is a fairy chess piece that can move any number of steps as a knight in the same direction. The nightrider is often represented by a symbol similar to the knight's icon, but altered in a way to indicate the additional straight-line motion. In this article the nightrider is represented with an inverted knight, and notation N (in which case the "knight" is abbreviated as S for German "Springer"). The nightrider was invented by T. R. Dawson in 1925, and
Dabbaba (chess) Dabbaba (chess) A dabbaba (or dabaaba, dabbabah) is a fairy chess piece that jumps two squares orthogonally (the directions a chess rook can move), leaping over any intermediate piece. In notation, it is given the symbol D. The dabbaba is a very old piece, appearing in some very early chess variants, such as Tamerlane chess. The name "dabbaba" (Arabic: دَبَّابَة) means "tank (vehicle)" in Modern Arabic. In older Arabic, it referred to a type of medieval siege engine designed to shelter men who are digging a hole in enemy fortifications (Latin: "vinea"). The name has sometimes been translated as "war