Game Of Thrones: 14 Things You Learn Rewatching Season 3
12. The Warlocks Just... Give Up?
Daenerys' Season 3 storyline starts off in an extremely creepy fashion, as a young girl hands her a ball to play with, which turns out to be a manticore, with the aim of killing Dany before Barristan Selmy saves the day.
The girl then shows her more twisted face and disappears into the water, with it being commented that she was sent by the warlocks of Qarth, who are apparently out for revenge (which makes sense, given Dany's actions in Season 2).
After that, however, the storyline is just completely dropped. There's no re-emergence of the girl; the warlocks are never mentioned again. They do have an expanded role in the books, where a number of them who set out to get revenge on Dany are captured by Euron Greyjoy, but we probably shouldn't expect him to turn up at King's Landing with four warlocks to go with the Golden Company.