The Crawling Chaos

At the beginning of each opponent's upkeep you
may pay {2}. If you do, look at the top card of
that player's library, then you may put that card
on the bottom of that player's library.
{t}: Reveal the bottom card of target opponent's
library. If its a spell with mana value less than the
number of cards in your hand you may cast it
without paying its mana cost.