Reveal the top nine cards of your library and separate them into three piles. An opponent chooses one of those piles. Put the rest of the piles on the bottom of your library in any order. Cast one card from the chosen pile without paying its mana cost, put one of them into your hand, and the other on top of your library or into your graveyard.
See Challenge # 163.
Looking for 'nine' I tried a bigger variant of fact or fiction or gifts ungiven. Unfortunately it's still rather clunky, any suggestions for simplifying it?