Ghost traps are traps that only appear on levels 21 and 22 in Knight Trap. They are one of two traps not to make an appearance in Office Trap, the other being the X2 Traps.
Ghost trap buttons have an icon of a white-coloured ghost with two brown eyes. The ghost is white, has a tail like head and waist, and white arms. The facial features of the ghost include an orange nose, cheeks, brown eyebrows and mouth. Ghosts activated by ghost traps have two transparent spheres around them.
Ghost traps are made out of only wood, as they do not appear enough times in the game to have brick buttons. Ghost traps when activated will cause a ghost to rise up out of the button. Ghosts will move horizontally and slowly up and down. They can be easily passed by running under them when they move up.
The ghosts do not move up through platforms or down under platforms, but stay between the top and bottom platform. They are quite easy to avoid, and because of this the player's knights will usually not get killed by them. If a knight makes contact with a ghost, however, he will turn to stone and crumble into dust.