Legendary Dissapointment

As soon as legendary raid went live I did an Articuno battle the first chance I got. I barely chipped a quarter of its health after 5 min. Even with 4 or 5 people, the maximum I ever see even any large parks thats not enough to even do a tier 4 raid much more tier 5. Legendary raids are sort of a joke for me a somewhat rural player. I can see 2 pokestops and a gym from my house, but nothing spawns better than the occasional jumpluff or rarer victribell. I have heard people say that when gen 3 is released the spawns will be over saturated and wholeheartedly agree, it will be to hard to find thaw Pokémon you are looking for, and the option to switch generations seems unreasonable so I thought about the nest migrations. What if sort of like the nest migrations the regions would migrate every week or so, so one week your entire town, egg pool, and raids would only be Pokémon found in a specific region. For example if your town was Kant you would have the original 151, but if you were Alola you would have magikarp, the aloan variants of meowth, grimer, raichu, then corsola, snorunt, and all the other Pokémon you can find in the core series sun and moon. If more generations are released this is how I think it will happen

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