Does this work? I'm assuming you choose the new target for the copy during resolution of the Dualcaster Mage ability rather than when the ability is put onto the stack.
Yes, this works. Because, as you stated, the new targets of the copy are chosen when the trigger resolves, and by that time, the Mage is already in the graveyard and a legal choice.
Cast Unearth on something.
Cast Dualcaster Mage with Unearth on the stack.
Dualcaster Mage trigger goes on the stack targeting Unearth.
Sacrifice Dualcaster Mage.
Dualcaster Mage trigger resolves, putting a copy of Unearth onto the stack that targets Dualcaster Mage now in the graveyard.
Unearth copy resolves, returning Dualcaster Mage and allow the sequence to repeat.
Does this work? I'm assuming you choose the new target for the copy during resolution of the Dualcaster Mage ability rather than when the ability is put onto the stack.
Former Rules Advisor
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