Cards like Roaring Moon ex are immensely powerful because they can knock out any Pokmon without caring about its HP, while cards like Pecharunt ex are amazing for closing out matches where the opponent has taken a significant amount of prize cards throughout the game
Its very difficult to remove, and drains your opponent for 2 when it dies (usually 4, including the creature that was sacrificed to pay the ward cost)
however, their serialized variants are only in Collector Boosters
Think of an insult so vicious, so vulgar, that you hesitate to speak it aloud
And as mentioned above, there are only two of the Wizards Commissioned Presentation Blastoise
You want to focus on big, impactful creatures that really shake up the board state upon entering the field, and who can continue to disrupt the game as long as they are on the field (or, possibly, by coming back from your Graveyard again, and again, and again) Protecting Yourself from an Early Grave, and Knowing Your Match-ups Reanimator decks also dip into forms of spot removal