Once you cast Miirym, the game quickly pivots to my opponents needing to either kill Miirym or kill me before I untap and start putting nontoken Dragons onto the battlefield
On top of that, it buffs your artifact creatures and heroes based on the number of artificers you control or have in the graveyard, which can scale fast in the right build
To secretly choose the numbers, you and the target opponent should each write down your choice of 1, 2, or 3 without showing them to anyone else
The Fair decks simply aren't equipped to deal with the kinds of threats that Ramp deploys
This time, I've assumed that you, in some fashion, get to see 2 more cards than normal over the course of 9 turns - whether through something like a Divination, a Tormenting Voice, a scry 2, or something else