So Lady Sansa's Rose says After you win a challenge in which you control a Knight character that is attacking or defending alone, that character gains 1 power. (3 power instead if you control a Lady character.) (Max 1 per challenge.)
If I attack with, say, the Knight of Flowers and the Hound, and I win the challenge so the Hound is returned to my hand via his own forced reaction, am I allowed to trigger Lady Sansa's Rose as the Knight of flowers is currently my only attacking character, or does the card/game remember that Knight of Flowers was not declared as a lone attack and thus the triggering condition for the event is not met?
I guess this basically boils down to; when does the game verify that a character "is attacking or defending alone". My instinct would be that it is checked when Lady Sansa's Rose is about to be played but I'd like confirmation.