When this artifact enters, look at the top five cards of your library. You may reveal a blue or artifact card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
, , Sacrifice this artifact: Creatures you control can't be blocked this turn.
Because the last ability of Tezzeret’s Gatebreaker doesn’t change the characteristics of any permanents, the set of creatures affected by it is constantly updated. Creatures that come under your control later in the turn can’t be blocked.
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