The number of War of the Spark cards showing up in winning Modern decks is pretty staggering, especially considering the set was only officially released last week
However, the best general tutors are very expensive: cards like Vampiric Tutor, Demonic Tutor, Finale of Devastation, all these are in the double digits
In theory (although not in practice, because box distribution isn't truly random), a booster box could contain zero mythics and all bulk rares, or it could contain a complete set of foil mythics
The policy also allows for special-purpose reprints, like oversized promotional cards that arent meant for regular gameplay
Not only that, but with Asceticism around, we get to regenerate any threat even before a board wipe, and it shouldnt be hard to regenerate three or four creatures during combat