Ghost is, without a doubt the most creative of all 18 pokemon types. I mean look at this shit, a handful of three stage lines and they overwhelmingly aren't starters only. And even then all their designs are the upmost enjoyable aesthetic. Not just objects with creepy aspects. Of course, we also have four ghost/grass lines and each one still feels unique.

Even beyond the starters, it's hardly ever the same shit with few exceptions. Ghost objects, ghost dolls, more ghostly phantoms, more ghost legendaries.
What's also original? The ghost lamps, the sarcophagus, the spooky marowak, the possessed oven and the fireworks clown.