Oberyn Martell : I'm sorry about your grandson.
Tywin Lannister : Are you?
Oberyn Martell : I don't believe that a child is responsible for the sins of his father... or his grandfather. An awful way to die.
Tywin Lannister : Which way is that?
Oberyn Martell : Are you interrogating me, Lord Tywin?
Tywin Lannister : Some believe the king choked.
Oberyn Martell : Some believe the sky is blue because we live inside the eye of a blue-eyed giant. The king was poisoned.
Tywin Lannister : I hear you studied poisons at the Citadel.
Oberyn Martell : I did. This is why I know.
Tywin Lannister : Your hatred for my family is rather well-known. You arrive at the capital, an expert in poisoning. Some days later, my grandson dies of poisoning.
Oberyn Martell : Rather suspicious. Why haven't you thrown me in a dungeon?
Tywin Lannister : You spoke with Tyrion in this very brothel on the day that you arrived. What did you discuss?
Oberyn Martell : You think we conspired together?
Tywin Lannister : What did you discuss?
Oberyn Martell : The death of my sister.
Tywin Lannister : For which you blame me.
Oberyn Martell : She was raped and murdered by the Mountain. The Mountain follows your orders. Of course I blame you.
Tywin Lannister : Here I stand, unarmed, unguarded... should I be concerned?
Oberyn Martell : You are unarmed and unguarded because you know me better than that. I am a man of reason. If I cut your throat today, I will be drawn and quartered tomorrow.
Tywin Lannister : Men at war commit all kinds of crimes without their superiors' knowledge.
Oberyn Martell : So you deny involvement in Elia's murder?
Tywin Lannister : Categorically.