Scroll of Veturius

{t}; Add {w}, {u}, or {b}. If this mana is used to cast a noncreature spell, that spell gains cascade.
{7}, {t}, Sacrifice Scroll of Veturius; Exile the top ten
cards of target player's library, you may cast up to two
target noncreature spells exiled this way without paying
their mana cost.
"Mind your tone, for I can reshape your destiny just as
easily as I can change my form."
~Veturius, Augur of Destiny