Defender has two characters in play (say Sansa and Cat) and loses a military challenge. One of his characters has a 'kneel save card attachment' (I think one of the dire wolves is that). (say Sansa)
Can the defender say, "I choose to kill Sansa, and ohhhhhlookie there, I'll just kneel this card instead"
My instinct says in such a situation you have to kill a character that can be killed unless Sansa is the only character out. But what's the real rule?