>>725125985
>I recall reading somewhere that she has to get to like, 10%HP or lower for the option to pop up, but if you deal a bunch of damage you can just straight up kill her without ever getting it. In short, be worse at the game.
Foremost Spine expert here. Common misconception, the way to spare her before 1.5 was to get her to 50 HP and wait a turn. This was actually a bug because Frankie forgot to set her status to immortal correctly. The 50 HP text also coincidentally fired the event accidentally so no one noticed and assumed that was intended behavior. That's been fixed, so the way to spare her to to just "kill" her once she says "home is where the heart is."