In a Arena Cube match the following situation occurred. Opponent played Tajic, Legion's Valor and attacked only with the creature it generated. The attack prompted an instance of Exalted on the stack with the image of Ignoble Hierarch, even though the opponent only had a face-down creature on the board. I don't understand how this could have happened - my only guess is that the face-down creature was actually an Ignoble Hierarch, but somehow his Exalted ability still triggered.