Yes, unfortunately the 20th anni. Pokemon are impossible to get.
The Pokemon distributed (Mew, Celebi, Jirachi, Darkrai, Manaphy, Shaymin, Arceus, Victini, Keldeo, Genesect, and Meloetta) were unavailable past 2016.
This means that the only way to get them like Staka said is through hacking and trading.
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