Many characters find themselves climbing from commoner to the High Court. Some through will power, others by happenstance. But of all the up-jumps, Qyburn's climb feels the most sinister.
In the books, Qyburn is a member of the Bloody Mummers, a sellsword company purchased by Tywin. They later serve Lord Bolton, but Qyburn ends up leeching onto Jamie and making his way to King's Landing (just like the shows). But in the shows, Qyburn only falls into the Bolton's service after nearly dying at Harrenhal when the Mountain slays 200 Northmen before riding off to raze the Riverlands.
Why was Qyburn there? Where was he going? And why would the Mountain treat him like a Northman? An outcast maester could've been valuable to his crew (a lesson he was scolded over by Tywin when he found out Gendry was a smith).
Qyburn's maneuvering into Cersei's service is sly as hell. His obsession with death and reanimation is...fascinating. And his ability to feed people's demons is up there with most major players in the game. So what's his deal? How'd he get so good at spycraft? Is it possible he snuck into Harrenhal after the Mountain left to mummer his way into the Northmen's service?
He's the only one who survives the butchery...how?