My opponent plays "The Things I Do For Love" targetting my tyrion (he pays 5 gold for the event). COST X; Text: challenges action: kneel your faction card to choose a character with printed cost X or lower controlled by an opponent and return it to its owner's hand
I have "Hand's Judgment" in hand (COST X; text: interrupt: when the effects of an opponent's event would initiate, cancel those effects. X is that event's printed cost ).
Do I have to pay 0 because the printed cost X of "the things I do for love" is considered zero, or do I have to pay 5 because my opponent paid 5 gold?