'Game of Thrones': Jason Momoa Sent Showrunner to Hospital With His Powerful Slap

Jason Momoa took his role as Khal Drogo a bit too far during season 2 of Game of Thrones. Yes, his character was technically dead at the time, but he had returned to the series for a cameo in one of Daenerys Targaryen's dreams.

While it was only a quick appearance for the actor, he decided to stretch it out a bit with some celebrating alongside Emilia Clarke, Alfie Allen, David Benioff, and D.B. Weiss. It was a moment that Benioff wouldn't forget because Momoa ended up sending to the hospital -- in a fun way.

The incident revolves around some drinking and Momoa playing against Benioff in "the slap game." The showrunner recounts the tale in HBO's Backstories web series, traveling back to that night in Belfast, Ireland.

"Jason was one of our favorite people ever on the show, and very strong. And that's not TV makeup -- in real life, he's just a big strong dude," Benioff says in the video. "So, I'm looking at Momoa and Momoa's talking about beating someone at the slap game. I was like, 'I'll take you at the slap game.' I was like, 'I'm going to challenge the Khal because if I beat the Khal, I am the Khal."

This does not end well.

The pair down a few beers and then begin playing the game. It consists of one person slapping the other's hands until they miss, something Steven Seagal showed off in a few of his films. Soon enough, Benioff finds out his mistake.

"I looked over and his hands were bright red," Weiss mentioned in the clip. "He was still going, and that was when all of us decided to put our conversation on hold to watch this contest."

Benioff adds that he looked into the eyes of his opponent and saw "no mercy," but still refused to quit out of some foolish pride. The result would be a rough morning the next day. His hands doubled in size and he went back to Los Angeles, hoping they'd get a little better on the plane ride home. This didn't happen.

Benioff's wife, actress Amanda Peet, send him directly to the hospital for a check-up.

"Her diagnosis was that Jason Momoa had squished my hands," Benioff said before adding that he only had to get a few x-rays. His final thought? "Don't challenge the Khal."

The funny thing is that Momoa's likely lost some of that power now that he's shaved off his trademark beard. That means he'll be weak for the few hours he's without it. But the time apart from the beard is for a good cause.

"I'm shaving this beast off, it's time to make a change. A change for the better...for my kids, for your kids, the world. Let's make a positive change for the health of our planet. Let's clean up our oceans and our land. Join me on this journey. Let's make a switch to INFINITELY RECYCLABLE aluminum. Water in cans, NOT plastic," Momoa wrote alongside a video of him shaving.

Far better than sending your former boss to the hospital with swelled, swollen hands.