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this rug in the train station of a recent screenshot shows several of the recently showcased dynamic Kanto pokemon as well as Gengar and Machamp.
One of the leaks showed a mach amp with 6 arms so this is all but confirming that these two will also get Gigantamax forms.
Hopefully the one hidden behind the chair is Lapras per the Affleck leak but its probably just eevee because waterfags are being blue balled by Galar after getting so much from Alola