|The Red Viper and The Mountain, by ~Jyvblamo via deviantART|
This chapter is really packed, but it comes to one of those heartbreaking conclusions that GRRM has become so famous for.
So many of us just assumed that Tyrion was going to come out on top yet again, because so much of this situation mirrored what happened while he was in the Vale. His champion then, Bronn, was similarly lightly armored and relying on his speed and intelligence just as much as his strength and skill to win the day, as Oberyn does here.
But as Brendan says, Oberyn's pride is his undoing; if he had resisted the urge to force Gregor to confess, if he had been satisfied with just taking him down and foregone the grandstanding, maybe he'd still be alive. Sadly, not only is Oberyn dead, but we're not even necessarily sure that Gregor also died. It seems very Martin-esque to have the good guy die and the bad guy live, doesn't it? Guess we'll find out.