While originally created with artifacts in mind, the concept of "imprinting" something onto a card and then having the card's effect vary based on what was imprinted is a flavorful one that can span many use cases
This black saga handles threats on the board and in the graveyard over several turns and does it faster with proliferate effects
Primarily used alongside Valakut, the Molten Pinnacle in combo decks, Primeval Titan is powerful enough to show up in the current iterations of Amulet Bloom as well
You can often double your mana by tapping out in your main phase, or you can attack first to force a player you suspect to be holding countermagic to tap out
And since these are premium cards that only come out of one specific product, there aren't a lot of them in the market
Since this treatment is so expensive and collector-focused, having all six stones would be quite the collection