Vessel of Nascency

The split between selection and self-mill is what this little enchantment is built to exploit. One green buys the enchantment, and later cracks it to dig four deep, keep one card, and put the other three into the graveyard. That gap (cheap to play, more to activate) is the whole bargain: the delay buys card selection while stocking the graveyard as a deliberate byproduct rather than a cost. This is not card advantage. You spend the Vessel and the activation to convert the top four of your library into one card in hand and three in the yard; the deck nets nothing, it just chooses better and fills the bin. For a fair deck those three cards milled are tuition paid for the dig. For a graveyard deck they are the point, and the keeper is gravy. The selection clause is pointedly restrictive: it can retrieve only an artifact, creature, enchantment, land, or planeswalker, the five permanent types named on the card and nothing else. A deck built on instants and sorceries that reveals four of them gets nothing back and mills itself for free, so the card sorts itself toward permanent-heavy strategies that want bodies in the bin. That single restriction is its discipline: it cannot smooth a spell-based draw, only a permanent-heavy one. Enchantments that defer selection for a turn of tempo are an old idea, but the dual identity here (dig for one camp, stock the yard for another) is why a do-nothing one-drop finds a home in two very different decks at once.