Ruetir.com, in Pokémon Purple and Pokémon Scarlet Mass spawns are important because if you defeat many Pokémon in a row of the same type, you increase the chances of getting a Shiny one.
Starting from this base, you should know that Shortly after starting the adventure, the SmartRotom will notify you of massive apparitions in a specific area, it will indicate it on the map. Basically it will indicate the exact place and the Pokémon that is appearing massively.
These appearances may be in different biomes on the map:
TownMountain, Snow, Rock, Cave, Mine, Subsoil, Ruins, DesertRiver, Lake, Swamp, Beach, SeaGrass, Flowers, Forest, Olive trees, Bamboo
You also have to know that it can there may be several massive apparitions at the same time in different areas.
Now, to facilitate your search for shiny, Guinea Pigsgamer has made a Explanatory video to help you restart mass apparitions legally:
Fuente.
