Invasion of Vryn // Overloaded Mage-Ring

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When this Siege enters, draw three cards, then discard a card.
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{1}, {T}, Sacrifice this artifact: Copy target spell you control. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)