The owner of target artifact or creature with mana value 1 or greater shuffles it into their library. Then that player discovers X, where X is its mana value. (They
exileTo exile an object, move it to the exile zone from wherever it is. See rule 406, “Exile.” (CR 701.13) cards from the top of their library until they
exileTo exile an object, move it to the exile zone from wherever it is. See rule 406, “Exile.” (CR 701.13) a nonland card with that mana value or less. They
castTo cast a spell is to take it from the zone it’s in (usually the hand), put it on the stack, and pay its costs, so that it will eventually resolve and have its effect. A player may cast a spell if they have priority. See rule 601, “Casting Spells.”
To cast a card is to cast it as a spell. (CR 701.5) it without paying its mana cost or put it into their hand. They put the rest on the bottom in a random order.)