https://techcrunch.com/2017/10/19/pokemon-gos-halloween-event-will-bring-new-pokemon-double-candy-and-more/

Just a few days ago we wrote that new Pokémon were seemingly just about to land in Pokémon Go timed alongside a Halloween event — and hey, what do you know: Niantic has just confirmed it.

The first Generation 3 Pokémon should start showing up as early as tomorrow, October 20th, at noon Pacific.