Subrule · Chapter 7
cr:7.3.2c
If a player declares two or more defending cards for an attack-target, they decide the order those cards are declared and become defending.
Example: Flic Flak has the text “If the next card you defend with this turn is a card with combo, it gains +2{d}.” If a player declares two or more cards, they choose the order they become defending, and thus which of those cards Flic Flak’s ability will apply to.