Gengar is a mischievous Ghost/Poison Pokémon not tied to a specific being. Gengar Pokémon (#0094) is one of the most popular, and people love it a lot. Gengar’s origin as a ghost is not explicitly confirmed in Pokémon lore.
For detail visit: https://larvesta.com/gengar-pokemon/
For detail visit: https://larvesta.com/gengar-pokemon/