In Season 6, Episode 8 of Game of Thrones, Cersei seemingly lost her last hope when Tommen outlawed trials by combat.
For a moment it seemed she had no more moves left – and then this little exchanged happened between her and Qyburn.
There's a really good chance he was talking about the caches of wildfire stashed around the city from Mad King Aerys's reign.
Bran's vision focused on them for a reason – and this could be it.
A popular fan theory suggests Cersei will become the Mad Queen and unleash wildfire – and after this week's episode, it's looking more likely than ever before.
Cersei is more desperate than she's ever been before – and we know from her past actions she'll do drastic things when she's feeling desperate.
Cersei had been intending to use wildfire during Season 2, before Tyrion stole it for the Blackwater. If Qyburn has discovered the secret stash underneath the city, Cersei probably wouldn't hesitate to use it.
Her and Loras's trials will happen soon – likely in Episode 10, given Bastardbowl will be the focus of 9 – and what better opportunity is there for Cersei to kill all her enemies in King's Landing in one go?
Because this is Game of Thrones, and everything comes at a price, there's a good chance Tommen will somehow get caught up in the fire and also die...
...fulfilling the prophecy that Cersei would lose everything she held dear, including all of her children, just in time for Jaime to show up in King's Landing, become the valonqar ("little brother" destined to kill her) and end her life as he ended the Mad King's.
Many think he'll then kill himself or perish in the wildfire, but there is another possibility. With Tommen dead and all the Baratheons gone (except bastard Gendry, still out rowing somewhere), there'd be no one left to inherit the throne. Some Reddit users argue it may fall to Jaime.
Or maybe Jaime will die, and the throne will be left empty just in time for Daenerys to swoop in on her dragons and claim it for herself.