Niantic has announced that they will be doing a special, Halloween, ghostly themed event for Pokémon Go.
Starting on October 20 and running through November 2, players will begin to see the arrival of Ghost-type Pokémon from the Hoenn region. These will include Sableye, Banette, and many others. Additionally, other Ghost-type Pokémon will increase in number. Pikachu will also be wearing a specially themed costume for the duration of the event.
Finally, there will be increased Candy rewards, special boxes in the shop, and a new avatar item available for players as well. Pokémon go is available now for iOS and Android devices.