'Game of Thrones' Star on Sunday's Duel: 'The Show Upped Its Game'

Mountain Oberyn Game of Thrones - H 2014

Update: read the full Q&A here.

It's almost time for "The Mountain and The Viper," and one of the actors involved promises Game of Thrones fans won't be disappointed by Sunday's big battle.

The episode will pit Oberyn (Pedro Pascal) against The Mountain (Icelandic strongman Hafthor Julius Bjornsson) in a battle to the death as part of Tyrion's (Peter Dinklage) trial by combat.

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"The show upped its game as far as its own production design — which it's already incredible at," Pascal, tells The Hollywood Reporter. "To be at the center of it, as a character piece in the middle of this world, it was amazing."

Pascal adds "there were extensive fight rehearsals" with Bjornsson to get the scene right.

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Others involved in the episode also tease that it will be massive. Director Alex Graves told THR  back in March that what comes in Sunday's episode (as well as in the June 15 finale) makes the Purple Wedding seem almost small in comparison.

Check back to THR.com/GoT Sunday night where Pascal and his onscreen nemesis will spill more details about their trial by combat. In the meantime, check out our theories about what's to come.

Game of Thrones airs at 9 p.m. Sunday on HBO.

Email: Aaron.Couch@THR.com
Twitter: @AaronCouch