If Quentyn Martell would be killed, instead attach Quentyn Martell to your House card as your only agenda with the text: "Unique [Martell] characters you control gain vengeful. Response: After 1 or more characters stand for vengeful, draw one card."
if Quentyn would be kiiled during a challenge, does he attach to the house card and the agenda take affect immediately ... thus allowing other characters to stand for vengeful?
Or would he only become effective as an agenda from the next challenge onwards?
I get a little bit confused here - this is a passive and a replacement effect, but doesn't the card still go to moribund until the action resoves?