Have you been noticing rather… large Pokémon on your map in Pokémon GO? Evolve species, even? You may have thought yourself lucky, but there is more to this than pure happenstance. Encounters with evolved species have seen an uptick since the introduction of Seasons in December 2020 with the Season of Celebration but now, the new season titled Season of Legends, is spotlighting evolved spawns even more.
Before the release of Shiny Pokémon in Pokémon GO, the rarest possible encounter you could get in the game was a powerful, evolved species. People would absolutely lose their minds if they saw a wild Dragonite pop up on their map, and rightly so. That era of the game felt like anything could and would happen. That continued into the release of the Johto region with Pokémon like Tyranitar and others spawning in the wild.
Now, years later and after a spawn of time when wild evolved spawns seemed to be extremely limited, this occurrence is possible once again and even, it seems, highly boosted. I have personally casually opened my phone at home to be greeted with Ampharos, Ursaring, Raichu, Exploud, and more.
Another interesting feature is now certain evolved spawns can be Shiny. This is mostly thanks to Mega Raids, but one evolved species actually got a Shiny release thanks to the Season of Legends. Arcanine was reported to have been encountered by many trainers in its Shiny form at the start of the season. This undoubtedly ties into the season thematically, as Arcanine is classified as the "Legendary Pokémon" in its Dex entry.
Other Pokémon that can be Shiny now in the wild thanks to the unlocking of their Mega forms are Charizard. Blastoise, Venusaur, Beedrill, Ampharos, Abomasnow, Gengar, Pidgeot, Houndoom, and Gyarados. These Pokémon have been observed to have a Shiny rate of approximately one in 60. It cannot yet be determined if the same applies to Shiny Arcanine.