Although this feature is a delightful surprise for fans, it doesn't function when the Pokdex is organized by set, which restricts how many times it can be used
Again, here's an incomplete list of Ancient Stirrings decks: Ironworks Tron Hardened Scales Whir Prison Lantern Control Amulet Titan or Bant Eldrazi Again we see a wide variety of decks, of course all involving artifacts or Eldrazi because that's the deck-building restriction, but running the gamut from beatdown to big mana to control/prison
7: You get an emblem with "At the beginning of your end step, create three 1/1 white Cat creature tokens with lifelink." Legendary Planeswalker - Ajani Basri Ket +1: Put a +1/+1 counter on up to one target creature
This is exactly what got it banned in Kaladesh Standard only a few months after its release
Not only that, but there are multiple TCGplayer orders buying dozens of this card at a time
They haven't undergone the rules scrutiny that most Magic cards have gone through, so if you have further questions, Wizards has also put out Release Notes to cover some of the situations you could encounter
