Warning: Spoilers ahead.

Millions of "Game of Thrones" fans were thrilled by the surprise twist at the end of the last episode — when Arya Stark finally killed the Night King using her Valyrian steel dagger, ending the Battle of Winterfell. Maisie Williams, who plays Arya, knew that not every fan would be pleased with the decision, but it turns out that even her boyfriend thought another character should have gotten the honor.

"It was so unbelievably exciting," Williams told Entertainment Weekly. "But I immediately thought that everybody would hate it; that Arya doesn't deserve it."

Get Breaking News Delivered to Your Inbox

"The hardest thing is in any series is when you build up a villain that's so impossible to defeat and then you defeat them," she continued. "It has to be intelligently done because otherwise people are like, 'Well, [the villain] couldn't have been that bad when some 100-pound girl comes in and stabs him.' You gotta make it cool."

Arya and the Night King, seconds before she delivers the fatal blow. HBO

Williams also revealed that even her boyfriend thought Jon Snow should have been the one to deliver the fatal blow: "And then I told my boyfriend and he was like, 'Mmm, should be Jon though really, shouldn't it?'"

Some fans agreed, tweeting that it made more sense for Jon to kill the Night King given their history over the course of the show. After some fans accused Arya of being a "Mary Sue" — a term for a perfect character who lacks any flaws or weaknesses. Others came to her defense, even suggesting she should break up with her boyfriend. After all, Arya had been training for this moment nearly since the show's first episode.

Everytime a woman does something heroic people are so quick to call her a Mary Sue. So Arya Stark, someone who has been training 7 seasons to kill DEATH, is now one but Jon Snow survives The Battle Of The Bastards and Beyond the Wall the way he did and no one says a thing. 🙄🙄 — Days Of Future Pasta. (@ThePhoenext) April 30, 2019

According to the show's creators, they've known Arya was going to be the one to kill the leader of the Army of the Dead for around three years. "We hoped to kind of avoid the expected," creator David Benioff said during Sunday's "Inside The Episode." "Jon Snow has always been the hero, the one who's been the savior, but it just didn't seem right to us, for this moment."

Williams said she ultimately realized that her character deserved the big moment. "When we did the whole bit with Melisandre, I realized the whole scene with [the Red Woman] brings it back to everything I've been working for over the past 6 seasons," she said. "So then I was like 'F*** you Jon, I get it.'"

Carice van Houten as Melisandre and Maisie Williams as Arya Stark. HBO

Kit Harington, who plays Jon, said that he was also shocked, but appreciated the twist. "I was surprised, I thought it was gonna be me!" Harington said. "But I like it. It gives Arya's training a purpose to have an end goal. It's much better how she does it the way she does it...There's also something about it not being the person you expect."

Director Miguel Sapochnik echoed those sentiments -- he wanted the audience to be completely caught off guard. "So we follow Jon in a continuous shot I want the audience to think: 'Jon's gonna do it, Jon's gonna do it…' and then he fails," Sapochnik told EW. "He fails at the very last minute. So I'm hoping that's a nice switch that no one sees coming. "