@Chttrbx_ I mean there's too many risks here. If she offs Anastacius now with Lucas, then there is doubt cast on the royal family because it is TRUE that there is black magic traces on the emperor. If the nobles find that out, then Athy will also be stripped of any noble standing because she obviously knew and tried to hide it. The biggest risk here is having her father be outed, not Anastacius being left alive from Ahty's viewpoint. Because if her father is incriminated anyway, he will fall eventually, and so will Athy. Lucas can lie, but if they ask for other imperial magicians to corroborate what has the emperor sick, then they could find out there is proof of black magic anyway, and would invalidate his position, and then Athy wouldn't be able to fight back properly. Then both Anastacius AND her family go down, which is not ideal either...
Athy was thinking the whole time, but she also does NOT have the full picture. She knows Anastacius' overall scheme, but he has also clearly been planning so far back with the Alpheus family, that there are huge holes regardless of what she knew from the original. She had no idea the Alpheus family was colluding with Anastacius. She has no idea what other things he might have done in the background to grip the other nobles by the balls. While it is bad that he leaves now, she has no idea how much better or worse it could be, especially if her father is outed. If Anastacius stays, he could demand Lucas to reveal the emperor anyway, and the nobles would agree, even if Anastacius gets taken down. It's better she cures her father first so there is no implication of black magic before going after Anastacius, because the nobles obviously want the emperor's input anyway; how bad does it look that a serious situation like the emperor's own half-brother and true claim to the throne appears, but the emperor himself does not come out to address the situation?