IGN's Ryan Dinsdale asked the developer Creatures Inc., but it declined to confirm one way or the other - and Dinsdale points to reports from Youtuber PokeNinaa and other players suggesting the cards are generated before you've chosen from the carousel
It departs through the streets fissures with a sound like gravel pouring into a pond
Not only can he loot through your deck, draining the entire table for one life if you discard an instant or sorcery, but he can then recast said discarded spells from your graveyard with his second ability
Some of the best ways to get this kind of value are cards with enters abilities
The scry every turn is also a powerful part of this defensive mechanism, making sure you hit land drops or find gasoline on just about every draw step
And unlike most effects, Maiden of White never banishes herself after using this effect, so you can use it continuously throughout the Duel