Quoted By:
Mew is the reason Mewtwo exists and it's first official event is being found on the abandoned old island
Celebi's actions are why Giovanni didn't join up with his comrades at Goldenrod
Deoxys was the reason Zinnia went on her quest in the first place unbeknownst to her and before that it's officially found in Kanto via a ridiculous side quest
Acerus is the creator of Palkia,Dialga and Giratina
Shaymin is mentioned but not named by the golthic lolita girl who partners with you, she even appears again once you get Oak's letter
Victini is just hanging out in the statue of liberity in Unova
Meloletta was attracted by the song of the barfly
Genosect is a Team Plasma experiment gone wrong
Keladeo is the adopted child of the three sword beasts
Gen 6 and onwards didn't even try to tie their mysticals to the lore of the region they were in let alone even have NPCs mention them, everything we know about them comes from the anime movies or information from the dex, Diance,Hoopa and Volcanion and gen 7 made it even worse, Marshadow, Margearna, Zeraora, Meltan and Melmetal are all mystical pokemon yet none of them have anything tying them to Alola, Marshadow, Meltan and Melmetal were first seen in Kanto officially, Zeraora as of the new movie is first seen in Kanto or Johoto, they never really told us what region wind city is in and Margearna is a Kalos tied pokemon.
