It needs to go along with a theme though. Ninjask and Shedinja are based on Cicada which is known to leave sheddings behind that look like they left a clone of themselves behind. In the pokemon case shedinja is that shedding.
Rotom Fan With an Air Balloon YO DOG i heard you like yo Rotom's High. So i gave it a balloon so it can be fly while he high while he way up in the sky! Dog!