Nikolaj Coster-Waldau, best known to Game of Thrones fans as Ser Jaime Lannister, had a rough time with the response to the final season of his hit HBO show. Perhaps you’ve heard, but the final few episodes of Thrones were incredibly divisive, leading up to a finale that shocked and dismayed scores of viewers. As it was bound to! There was no way the most-watched episode of television in HBO’s history was going to please everyone. Still, the final season of the show got knocked so hard that the cast—per Coster-Waldau—couldn’t believe how “vicious” the backlash got.

“Every season has been intense in terms of the attention and discussion, but it was extraordinarily intense for a final season,” the actor said during a Saturday fan Q&A panel at Con of Thrones, a Thrones-themed convention, per HuffPost. “And we have this WhatsApp group, the actors, and I saw some people getting a little upset because some of the stuff is vicious, and if you make the mistake of start reading all that shit, because if you guys get really angry about something―I’m sure you did, some of you―so you write to each other and go, ‘Fucking assholes. This is so not what would happen! They ruined, they butchered George [R.R. Martin’s] world!’ It’s just fun for you, but of course some got a little upset.”

While some cast members have shared their own disappointment with the show’s ending, they still were surprised at the level of fan frustration. “There was that kind of weird feeling of, What the hell? We worked so hard,” Coster-Waldau continued. “I’m not asking anyone to feel sorry, by the way. That’s not what I’m saying. I’m just saying how it was to get through that whole thing.”

The brunt of the blame has been placed on show creators David Benioff and D.B. Weiss, with a number of fans accusing the duo of phoning in the final season so they can move on to create their upcoming Star Wars movies. At a separate panel, Coster-Waldau weighed in on that charge as well, defending the duo.

“For anyone to imagine or to think that the two creators of the show are not the most passionate, the greatest, the most invested of all and to for a second think they didn’t spend the last 10 years thinking how they were gonna end it is kinda silly,” he said. “And also know that they too read the comments. Even though you sit on your own and go ‘Fucking stupid writers! Assholes!’ They really, like everyone on Game of Thrones, every single person—and there are thousands—we worked our asses off to make the best show we could for the ending.”

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