Unbowed, Unbent, Unbroken - S5-E6
Continuity mistake: When the Sand Snakes attempt to kidnap Myrcella, as Nymeria Sand runs up to Myrcella to seize her, she is holding her large whip in her right hand. However, in the very next shot, the whip has disappeared, and Nymeria is now holding a dagger in her hand instead.
Answer: This is explained more in the book. Khal Drogo and his bloodriders do intend to help Viserys take the throne, however they do things in their own time. This is what causes Viserys's frustration. In the book, Illyrio Mopatis tells Viserys that he has already waited his entire life to claim The Iron Throne and that waiting a few more years isn't that big of a deal. The Dothraki are a nomadic tribe, which is largely why they have no interest in invading and sacking King's Landing. However, since Khal Drogo eventually grows to love Dany, her assassination attempt by the Westerosi compels him to seek revenge.
Phaneron ★