When it comes to how to get these cards, there's a few options: obviously you can open packs, but you can also spend Pack Points to buy specific cards, or use the (not great) Pokemon TCG Pocket trading system to swap with friends accordingly
Built for the Grand Line Whether you collect, compete, or both
Compared to the sickly green of Shiny Espeon, its no wonder it became a Johto darling
This cycle is nasty in Type Four (rules for it here - Type 4 - MTG Wiki (fandom.com)) where you have infinite mana so their casting cost is not a problem, but you can only cast one spell per turn
Since these counterspells require X mana, however, it's important that you use them very carefully
While any such list will have some subjectivity to it, I wanted to take a looksee, so I reviewed all 613 cards out there to make sure that my memory matched the cards available and I wasn't forgetting anything important