For for the transparent shaman objects, see Ghosting.
For the skill, see Architect.
“Ghosts” redirects here. For the minigame, see Ghosts (minigame).

Ghosts were interactive moving characters appearing in Halloween 2012 event maps. If a mouse touched one of them, the mouse will lose one out of 4 health points. They can only be killed with the mouse's wand by swiping at it for about 4 times. The ghosts also appeared in Grim's Mansion as a traced version but did not harm the mice in any way.