Knowledge Pool
{6}
Artifact
Imprint -- When ~this~ enters, each player exiles the top three cards of their library.
Whenever a player casts a spell from their hand, that player exiles it. If the player does, they may cast a spell from among other cards exiled with ~this~ without paying its mana cost.
Possibility Storm
{3}{R}{R}
Enchantment
Whenever a player casts a spell from their hand, that player exiles it, then exiles cards from the top of their library until they exile a card that shares a card type with it. That player may cast that card without paying its mana cost. Then they put all cards exiled with ~this~ on the bottom of their library in a random order.