A great deal of kudos needs to be heaped upon Charles Dance for his work in this role. An actor with a career three decades long (including the vastly misunderstood Last Action Hero), Dance brings sophistication and steel to this performance. It certainly doesnt hurt that he has such a great part to play. Tywin appears briefly in A Game of Thrones and A Clash of Kings, but it isnt until A Sword of Storms that he becomes a main character. His deer-skinning Jamie-lecturing intro in the television show establishes him perfectly, and some of the second seasons most compelling moments come from watching him interact with Arya at Harrenhal (none of that is in the books, by the way). Because of all that, his authority is felt more strongly in season three. After all, he is basically the most powerful man in Westeros. Thanks to Dance, Benioff and Weiss, this is most apparent.