Book of Vile Darkness

{t}: Pay 2 life and reveal the top card of your
library. If it is an instant, sorcery, or
enchantment, you may cast it this turn
without paying its mana cost. If not, you may
put it into your hand.
{p/b}{p/b}{x}, {t}: Exile the top X cards from
target opponents library. You may cast any
spells removed this way from exile, and you
may spend mana as though it were mana of
any type to cast those spells.