The two weve actually seen, Fatal Push and Young Wolf, ironically sit at the opposite end of the spectrum
A popular way for Pokmon to take advantage of the enthusiasm towards the trading cards is to release exclusive promotional cards that could only be acquired through certain means, like attendance of the Pokmon movie in theaters
8 Volcanion ex Helps Cycle Energy First Printing: Journey Together Cycling energy between Pokmon can occasionally be difficult in some decks, as cards like Energy Switch and Crispin do not fit in every deck, and most strategies do not have access to powerful energy acceleration engines like Gardevoir ex and Hydrapple ex
The first of these is called Paradox, and lets you put a +1/+1 counter on a target creature whenever you cast a spell from anywhere other than your hand
It doesn't have any specific rules associated with it
I don't mean like, rule 0 forbid them to use it, I mean mechanically