The Ghost of Harrenhal - S2-E5
Character mistake: When Renly and Catelyn are negotiating the terms of Renly's alliance with Robb, Renly calls Moat Cailin "Moat Caitlin." As someone who served as Master of Laws on King Robert's Small Council, he should know the correct name of the territory he is referring to.
Battle of the Bastards - S6-E9
Character mistake: When Theon and Yara are given an audience with Daenerys, Tyrion remarks to Theon that when they last saw each other at Winterfell, Theon was making jokes about Tyrion being a dwarf. The mockery was actually the other way around: Tyrion mocked Theon for being a glorified and subservient hostage of the Starks, as well as taking potshots at the foolish strategy of the Greyjoy rebellion.
The Last Of The Starks - S8-E4
Character mistake: Gendry gets declared as Lord Gendry Baratheon of Storm's End by Daenerys. But he refers to himself as Gendry Rivers - the surname given to bastards from the Riverlands. Gendry comes from King's Landing, and bastards from there are called Waters, not Rivers. Given that Gendry is not an acknowledged highborn bastard, he should never have had a surname in the first place.
Character mistake: Davos advises Grey Worm to claim land in the Reach and start his own house. Since Grey Worm is a eunuch, he cannot start his own house, as he cannot father children to pass his name and lands onto.
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 ★