Previous predictable "Pokémon GO" spawning nests have now been entirely randomized, meaning that Niantic has changed the way things worked for hard-to-find monsters. The spawning approach has deviated from the tactic of simply switching one type for another at fixed spawn locations.
According to Forbes, when Niantic transformed spawning nests in "Pokémon GO" in the past, there was a list of Pokémon that would change to a different series of Pokémon. For example, if a "Pokémon Go" player had a Dratini nest nearby, it would change to an Eevee nest, something that also happened to all Eevee nests worldwide.
The next "Pokémon Go" update then changed those Eevee nests to something else. However, when Niantic updated the game this time, it is no longer the case. Rather than a "Pokémon Go" player going and cross-checking on a list to identify which Pokémon is spawning, the system is now random.
Rarity has not changed per se, but "Pokémon Go" players no longer have a way of predicting what spawning nests have transformed into. The only way is to go out and look for the monsters themselves.
According to reports collected worldwide from players, there is no other correlation remaining other than relative rarity. "Pokémon Go" spawning nests that used to spawn Charmander now spawn other Pokémon such as Digletts, Abras, Squirtles, and Ponytas, among others, depending on where the players are.
Electabuzz nests can now spawn Pinsir, Nidoran, Onix, Cubone,Polywag, and others. As sad as it may sound to "Pokémon Go" cheaters, it is also a good thing. It means that trainers can now catch rare Pokémon quickly by accessing certain Pokémon in nests, which one would not expect them to be accessed from.
The randomization, therefore, makes "Pokémon Go" attractive by reducing predictability. According to The Silph Road, a Reddit grassroots network of "Pokémon GO" trainers, Pokémon evolutions are now spawning nests, which was not possible before.
Dedicated "Pokémon GO" enthusiasts are yet to figure out exactly what the change means, but provided it is true, players can now find evolved versions of preferred Pokémon far more often than before.
Check out the video below to discover more on "Pokemon Go" spawning: