Glimpse the Unknowable

Reveal the top X cards of each players library,
put them into separate piles, then target
opponent chooses a pile, you may cast cards in
that pile, and you may spend mana as thought it
were any color to cast it. Return the rest to the
top of their owners library in an order of your choosing.
You thought you would gain knowledge? How right
you were, and how naive to the truth.