These ghost stamps were designed to keep a kind of capture count for Ghostbusters equipment. Having little ghosts added with each capture similar to how they decorate fighter planes after successful missions. One of the ghost is based on the sprite from the NES Ghostbusters game. The other one was designed by JoeStrout back in the 80s when he made a little Ghostbusters program on his old Apple computer. I found both those sprites make excellent simple stamps that work really well for the ghost count markings.