Split the Earth

Kicker: {b}{b}{r}{r} (You may pay an additional {b}{b}{r}{r} as you cast this spell.)
Target player puts all cards on their board into a
pile, and shuffles that pile. Then, they take the
top X cards, where X is half the number of the
cards in the pile. If you paid the kicker, reveal
both piles. Choose one of the piles. That player
exiles all of the cards in the chosen pile. The remaining pile stays on the battlefield under their owners' control