Revealing mistake: When we see Joffrey get attacked by the dire-wolf, You can see his arm suddenly has padding underneath his jacket. (00:47:20)
Revealing mistake: Just after Jon is told he is confined to quarters, there is a shot of outside with snow falling. However the snow is actually rising. Indicating the shot has been reversed. (00:22:55)
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 ★