This week we’ve all been trying to figure out how Cersei’s going to game the system to win her trial by the Faith now that trial by combat is no longer an option. We know it’s probably going to be drastic, or at least more drastic than creating a goddamned zombie warrior. We also know, from Bran’s vision, that a whole bunch of Wildfire that’s currently hanging out under King’s Landing is going to go boom at some point. And we ALSO know from that vision that the last person who tried to use that Wildfire to destroy King’s Landing was killed by Jaime Lannister.
So let’s start putting the pieces together.
It’s likely that Cersei was having Qyburn’s “little birds” investigate how much Wildfire was left over after Tyrion’s use of it in the Battle of the Blackwater. The timing of when he brought up the topic, just after the right to trial by combat was revoked, would make sense that it was some drastic, alternate plan for her trial. A pit of Wildfire under the Great Sept would make sense. It would destroy the High Septon and his followers, which is definitely Cersei’s immediate goal.
The problem is the long term consequences. In the last couple of episodes, Tommen has repeatedly said that the Faith and the Crown are the two pillars that hold up the world. If Cersei takes out the Faith, it’s likely that the Crown will be severely destabilized afterwards. Or, worse, she won’t be able to keep Tommen from being at the Great Sept, and he’ll be killed in the fire as well, leaving no heir to the throne and completely upending the political structure of Westeros. The other issue to consider is that the last time someone threatened to burn King’s Landing to the ground, they were killed by Jaime Lannister. But Cersei’s never been great at thinking long term, and particularly not when this issue is so personal to her. The High Septon paraded her naked through the streets and has taken her son from her, in her eyes. He must be destroyed as soon as possible.
Jaime may have expressed admiration for Cersei’s fierce devotion to her children, that she would “start wars, burn cities to ash” for their sake. But if she accidentally ends up killing their last child as part of her plot to save herself it seems unlikely that Jaime would look kindly upon her intentions. And then, perhaps, we will see why season 5 opened up with Maggy’s prophecy regarding Cersei’s life: “And when your tears have drowned you, the valonqar shall wrap his hands about your pale white throat and choke the life from you.”
Cersei’s been afraid of the wrong brother this whole time.