Regarding Dynamax, Gigantamax and Tera

[neat eagle]

gigantamax is just a special dynamax

if a pokemon has the gmax mark then it takes the gmax form when dynamaxing

if not it just dynamaxes regularly

[neat eagle]

it wont gmax if it doesnt have the mark

but swsh's dlc lets you give pokemon the gmax mark

unless its melmetal (its gmax is locked to a home event)

there are also a few cases where a pokemon can have the mark but doesnt actually have a gmax

specifically one case is a raid event that had milcery that had the gmax mark

there is no gmax milcery so it will just dynamax normally

but once it evolves into alcremie it will gmax since gmax alcremie does exist

yeah since gmax pichu isnt a thing

so if that existed it would dynamax normally until evolution

i havent engaged with SV much but my understanding is that every pokemon has a tera type and can be terastalized in battle

and there are items to change the tera type into whatever you want it to be

specifically the ones that have a gmax form and would evolve normally

so pikachu meowth and eevee cant evolve if they have the gmax mark

iirc you can also remove the mark with the same dlc soup to evolve them though

i dont think they have any restriction on breeding they just dont pass down the mark