So Dynamaxing doesn't just increase their size, but change's some physical characteristics as well?
That's actually pretty interesting. That means there's more to it than just "Make 'em big and fight 'em."
This isn't Dynamax, it's Gigantamax which apparently is just better Dynamax(or rebranded Mega) exclusive to a select group of Pokemons. As in not even every members of the specie can Gigantamax, you need to capture a special one with the ability to do so.