Whenever an opponent casts a spell, you may reveal the top card of your library. If you do, counter that spell if it has the same converted mana cost as the revealed card.
MYTHICSPOILER.COM THE CYCLICAL MTG SPOILER
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KHANS OF TARKIR 
COMMANDER 2014
FTV: ANNIHILATION 
SPEED vs CUNNING 
MAGIC 2015 
CONSPIRACY 
MORE SETS
