Changes are coming to the Mega Raid rotation in Pokémon GO this January. Venusaur returns, Houndoom gets a boost, and a brand new Mega Pokémon enters. Let's dive into the full details here.
On the official Pokémon GO blog, Niantic posted:
Mega Charizard Y, Mega Blastoise, and Mega Abomasnow will be appearing in Mega Raids, with Mega Charizard Y becoming even more powerful from Tuesday, January 5, 2021, at 10:00 a.m. through Tuesday, January 12, 2021 at 10:00am local time. Mega Blastoise is also a prime pick to use in five-star raids this month, so make sure to stock up on Blastoise Mega Energy!
So there we have it. In essence, Mega Gengar and Mega Charizard X will leave Mega Raids in early January, leaving Abomasnow as the only current Mega Pokémon that will remain in rotation. Blastoise and Charizard Y return, but keep in mind that Charizard Mega Energy isn't divided between X or Y. Besides the raid difficulty and the visual difference, completing a Mega Charizard X and Y raid will yield the same results for trainers: a Shiny-capable Charizard encounter and Mega Charizard Energy.
Long story short, stock up on that Mega Gengar energy while you can!
On Tuesday, January 19, 2021, a certain Mega-Evolved Pokémon will make its Pokémon GO debut in Mega Raids! More details will come to light as we get closer to the date. Mega Venusaur and Mega Houndoom will also be appearing in Mega Raids beginning on January 19, with Mega Houndoom being even more powerful from Tuesday, January 26, 2021, through Monday, February 8, 2021.
After about a month out, Venusaur and Houndoom return to Mega Raids. It'll be very interesting to see which Mega Pokémon will join Mega Raids, but we certainly have a couple of theories. A couple of months back, a datamine found that assets for Mega Slowbro and Mega Aerodactyl had been updated in Pokémon GO. Perhaps one of those will be the mystery Mega.
On the other hand, that Mega will begin during the Hoenn Celebration week, so there could be a tie-in. Hoenn Pokémon capable of Mega Evolution include Blaziken, Gardevoir, Mawile, Aggron, Medicham, Manectric, Banette, Latias, and Latios.