Though the wind is clearly in her sails at the moment - after the defeat of the Greyjoys and now the successful siege of Highgarden - Cersei seems to be slipping ever closer to her doom. And if - when - it comes, it looks like it will be entirely her own fault, because she's reliving the last days of the Mad King.
Somewhat ironically, for all of her anti-Targaryen rhetoric, she appears to be Aerys reborn, and if she's not careful, she is destined to fall exactly the same way he did.
Already, the image of her burning her people in the Sept of Baelor to rid herself of her enemies drew an immediate, irresistible parallel between her and the slain former monarch. Remember Jaime's description of Aerys back in season 3? The Mad King “loved to watch people burn. The way their skin blackened and blistered and melted off their bones.” Compare that to Cersei's perverse enjoyment of the burning of the Sept and it's impossible to ignore the similarities.
Similar too is her repeated assertion that she is surrounded on all sides by enemies (though hers probably have more substance than Aerys').
The latest step in her journey to relive the sins of the Mad King was how she dealt with Ellaria and Tyene Sand, when they were handed over as gifts by Euron Greyjoy.
In poisoning Tyene and leaving her to die agonisingly close to her helpless, distraught mother, she mirrored the way Aerys killed Brandon and Rickard Stark in the early days of Robert's Rebellion. When Brandon marched South to storm King's Landing over the supposed abduction of Lyanna Stark, he was arrested, drawing his father South to help. Aerys murdered both of them in the presence of his knights, who did nothing, in a manner hauntingly similar to Cersei's murder of Tyenne and torture of Ellaria.
Aerys hung Rickard from the ceiling, burning him alive while Brandon was tethered by his neck and given the opportunity to free his father, if he could reach a sword just out of his reach. He strangled himself trying to reach the sword as his father cooked in his armour - an image of desperation that was very much recaptured in Ellaria and Tyene reaching out for one another after Cersei had poisoned the latter.
It's also interesting that the episode dropped in an intriguing idea about time being a fluid concept: Littlefinger's vague, poetic speech to Sansa - which was actually designed to embolden her as a leader - spoke of every eventuality playing out simultaneously. It seems the one of the great, manipulative minds of Westeros has realised that everything is a circle, rather than a linear progression, and that everything will be revisited sooner or later.
On top of that we saw Jon and Dany talking about their family history being relived in perpetuity (though Jon railed against it, because he's the only one who sees the value of resisting repetition), and Bran creepily reminding everyone that he is able to see past, present and future as if they co-exist. Time was a big deal in this episode.
If you don't pick up on all of that as a confirmation that Cersei will live out the Mad King's end again, you're not paying enough attention.
Unfortunately for her, that means that she's probably going to be killed at the hands of her brother, Jaime, who also killed Aerys. The seeds of doubt have been planted in his mind already, first by Cersei's alliance with Euron (who he obviously can't stand), and now with Olenna's speech about her being a monster. Sure, the revelation that Olenna was behind Jaime's death might have aligned him back to Cersei again somewhat, but it seems inevitable that they will be drawn apart when she refuses to absolve Tyrion of blame in the face of the facts.
And that likely means that Jaime will be forced to kill his sister/lover when her actions go too far. He might be a bad guy, but again we saw a flash of humanity in his insistence that Olenna would die without pain by poisoning, rather than by one of the Mad King-like suggestions Cersei made.
What do you think? Will Cersei become the Mad King reborn and be killed by Jaime? Share your reactions below in the comments thread.