The Orb of Eternal Winter

When The Orb of Eternal Winter enters the battlefield, draw two cards.
Whenever you draw one or more cards, reveal the top card of your library, if it is a nonland card, you may cast it for {2} less this turn.
{2}{u}{u}, {t}: draw cards until you draw a nonland card, then put all the land cards back and you may cast the nonland card without paying its mana cost until end of turn.
{t}: Add {u} or {s}.