Master of the books

Whenever an opponent draws a card, scry 1.
{4},{t}: Discard {x} cards, then scry {x} and lose {x} life. At the beginning of your next upkeep
draw {x} cards.
When Master of the books leaves the battlefield, create a black 1/1 rat creature token with menace, hexproof and "When this creature deals combat
damage to player scry 1 and lose 1 life"