As Jason Momoa was trying out for the role of mighty warlord Khal Drogo in HBO’s Game of Thrones, he read George R.R. Martin’s novel. He recalls his reaction when he reached the end of the book:

“I was reading it and I was like: ‘Holy s–t! F–k, I’m dead!'”

Indeed! Even as viewers were reeling from losing Sean Bean’s Ned Stark in episode 9, Thrones delivered a second heavy blow in Sunday’s season finale: The toughest character in Thrones died from an infected cut (helped along by a vengeful woman whose village Drogo’s army destroyed).

“When I read that Khal Drogo role, I was blown away,” Momoa says. “I couldn’t believe it was happening, I had to have that role. I was like, ‘Nobody is going to take that role from me.'”

Momoa had to learn the invented Dothraki language, which he memorized by thinking of each line of dialog as if it were music. Playing the stoic character was also more challenging than it may have looked on screen.

“People say it’s easy — ‘You’re just sitting there!'” he says. “But it’s extremely hard to be extremely intimidating, and say everything but not say anything.” (Read it again and you’ll get it).

The actor will be seen this summer in the big screen reboot of Conan the Barbarian, a coveted role that he says Thrones helped him land (the projects shared a casting director). He says he’ll miss being on Thrones, but encourages fans to stick with the show.

“It’s amazing what [George R.R. Martin] sets up,” he says of the novels. “Here’s your lead characters, you’re supposed to think about them one way, and you hate them, then you love them, and then they’re killed and it’s a whirlwind of emotion. All the little kids and even the smallest of characters just grow and grow and grow. He built a beautiful world. I’m bummed I’m not going back. To play Khal Drogo was phenomenal and I wished there was more stuff he could have done, I’m going to miss that character.”