Mega Venusaur will leave Friday, October 23rd at 6 PM Pacific and, up until that time, will be featured more commonly in Mega Raids. Following its departure, Niantic confirms that Pokémon GO trainers will still be able to earn Mega Venusaur energy by completing Field Research at Pokéstops. There will also be a Mega Venusaur-centric Timed Research in November.