User blog comment:Wilfred J. Pemberley/Six Things that Need to Die for RWBY to Live/@comment-4010415-20190903034110/@comment-39854843-20190903071504

To me, the main villain of early GoT comes down to Joffrey and Petyr. The reason being is that I define 'main villain' as the antagonist that is most central in causing the story's main conflict. Cersei, while certainly evil, is not intentionally central to the main conflict of the show. It's true that her ordering Jaime to push Bran from the window lead to the war of the five kings, but that was not her intention. We see that more clearly when she urges Joffrey to spare Ned Stark, in order to avoid war.

Joffrey, on the other hand, wanted war with The North, which is why he chose to behead Stark. And that critical action was the point of no return from which the war was inevitable. That is why I believe him to be GoT's true first main villain.

Though, you could argue that Petyr was the first main villain, since it was his plot to assassinate Bran, and initiate the war of the five kings. The problem with that, though, is that his plot ultimately failed, and also he was too recurring of a character to qualify as the main villain.

But you do raise good points, and I think it's important to realize that GoT is far more complicated of a show than most others, and has far more active villains than most others. Which makes it difficult to assign 'arch-villain' status to any one character.