pokemon 25th pikachu card V 2021 Anniversary Japanese Ultra Rare When your Pokémon V is Knocked Out Pikachu V SWSH145 - Holofoil

In addition to just jamming your deck full of Scarecrows, you can really go off with blink effects

While not the easiest decks to pilot, thanks to their mana values, with just a little effort, you can make a nasty air force that your opponent will be hard-pressed to deal with

If your opponent goes on the offensive, counter them by deploying Characters with their [Trigger] effect while replenishing your hand

There also seems to be some consistent limitations to the cards it appears on: either you dont have full control over when you can trigger proliferate, or the way you trigger it leaves you behind on board relative to the mana spent