>>35305369>Magearna>December 2015You mean Volcanion. Volcanion was revealed in advance because Magearna was the true Mythical Pokemon star. Magaerna got the usual February reveal.
Furthermore, you're comparing apples and oranges here. In December 2015, we already had an unrevealed Mythical Pokemon that was in Gen VI: Volcanion. Then February 2016 revealed the first Gen VII Mythical.
This time is different. Zeraora is the absolute last Gen VII Mythical Pokemon. We're not going to have a situation like Volcanion's in 2018.
Yes, a Mythical Pokemon could be revealed for Gen 8 in late 2018 like you said, but that is very unlikely since not even Magearna had been revealed that early.
