Garrity, the Betrayer

When Garrity, the Betrayer enters the battlefield
exile the top three cards of target player's library.
{3}{t}: Reveal a card exiled by Garrity, the Betrayer
at random. If it's a non-land card you may cast
it without paying its mana cost. If it's a land you
may put it onto the battlefield tapped.
Only activate as a sorcery.
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