Cauldron of Answers

At the beginning of your upkeep, exile the top card of each player's library face down, you may not look.
{b}, {t}, put a random card exiled with Cauldron of Answer on the bottom of its owner library: Deal damage to target creature equal to the converted mana cost of the card.
{u}, {t}: Exile your hand face down. Put all other card exiled with Cauldron of Answer into your hand. At the end of this turn, discard your hand.