Dreaming Hall

Whenever a player casts a spell, he or she exiles the top card of his or her library face down.
{4}, {t}: Each player chooses a random card exiled by Dreaming Hall and casts it without paying its mana cost. If a land card is chosen this way, that player instead puts it onto the battlefield under his or her control.
All the wonders in the world and all the magic in the mind.