Starting tomorrow, Tuesday, April 20th (otherwise known as 4/20), Niantic is bringing some Grass-type Pokémon back to Mega Raids in Pokémon GO. How apropos. Mega Venusaur and Mega Abomasnow will return, and one of them may just be helpful against an upcoming new Legendary Pokémon. Here are the full details.
Starting tomorrow at 10 AM local time, Mega Gengar and Mega Manectric will leave Mega Raids, making way for a new rotation. Joining Mega Lopunny, the one remaining Pokémon from the previous Mega Raid rotation, are Mega Venusaur (a Grass/Poison-type) and Mega Abomasnow (a Grass/Ice-type). Now, Mega Venusaur might be worth investing in, as it is part Poison-type and is currently the 16th best overall counter for Xerneas. It is widely speculated that Xerneas, a Fairy-type Legendary from the Kalos region, will enter Pokémon GO in May 2021 as the culmination of the Season of Legends, which has been lightly hinted at in a blog post and all but confirmed by the opening screen. However, I'd only suggest investing in Mega Venusaur is you don't have enough Gengar Mega Energy for a Xerneas raid rotation. Mega Gengar will take the second overall slot as a Xerneas counter as of this writing, while Mega Venusaur will take the sixteenth.
So far, this is the final Mega Raid rotation that has been announced by Pokémon GO. If Niantic sticks to recent patterns, though, I believe we can expect an announcement about May 2021's events and raids within the next week or so. For the past few months, the beginning-of-the-month announcements have alluded to a new release tied to an event. So far, Bleeding Cool has been able to predict the release of Mega Manectric due to its ties to the Charge Up event and Mega Lopunny due to its Easter Day release. Let's see if we can do it a third time when the next announcement drops, if Niantic does indeed continue to roll out one new Mega Pokémon every month.