Turns out, fake dragons can be just as dangerous as real ones.

While making the new live-action remake of How to Train Your Dragon, stars Mason Thames and Nico Parker, as well as writer-director Dean DeBlois, all walked away with some battle scars.

Like the animated original, How to Train Your Dragon follows Hiccup (Thames), an outcast Viking teen who learns the hard way that he’s not equipped to slay dragons, as is tradition in his village. So, instead, he changes history by befriending one of them, specifically a Night Fury he names Toothless.

In one scene, he takes his crush, fierce Viking warrior Astrid (Parker), on a wild ride on his dragon pal, and while the characters return safely to solid ground, Thames didn’t emerge from the scene unscathed.

“Every time I had to fly the dragon in the movie, I was on this gimbal thing, and it was like a giant mechanical bull,” Thames tells Entertainment Weekly. “And we were doing a scene where it’s me and Nico on the dragon, and Toothless is kind of going crazy and wild, and she’s trying to hold on. So we start the scene and [the gimbal] starts going, and it’s going, and it’s really crazy.”

He continues, “And then the dragon goes down. Normally, when the dragon goes down, [the gimbal] goes up. So I get down, I’m ready, and then the dragon goes up and the head smacks me in the chin, and three rod iron bolts smacked me.”

Like a pro, Thames says he continued with the scene, not immediately realizing the extent of the injury. That is, until the sequence called for Astrid almost to fall off, and promptly grab Hiccup’s face for support.

“They call cut, and I just hear Nico go, ‘Oh my God,'” he says, doing his best imitation of Parker’s British accent in the process. “She looks at her hands, and they’re covered in blood. Oh, no. I looked down and there’s a pool of blood on the dragon. And I go down and I look in a little mirror we had, and there’s a little chunk of my chin gone — and it sucked.” Thames had to get five stitches, but to add insult to injury, the stitches had to be redone because, as he puts it, “The doctor put the stitches in and then was like, ‘Eh, I can do better,’ and cut ‘em out and put ‘em back.”

Parker was a little traumatized from the experience, but not for the reasons you’d think. “It wasn’t my fault, really wasn’t my fault,” she insists. “But, from my perspective, what had happened right before he hit his chin is we were looking at my hands, because me and Mason would be up on that dragon for really quite long stretches at a time. And I remember my nails had gotten quite long and we’d forgotten to trim them or file ‘em or anything. So they were quite long.”

The next take called for her to grab Thames’ face, and before they called action, Thames joked that Parker was going to cut him with her long fingernails. “Then I’m looking at my nails and I’m like, oh my God, these actually, they wouldn’t cut him, but what if I accidentally dig or scratch him — and this is the golden child here. I can’t hurt him,” she says, laughing.

That very next take, Thames busted his chin, but Parker, who was seated behind her costar on the “dragon,” didn’t know that’s what happened at the time. She says she just remembers hearing him make a grunting noise, and next thing she knew, her hands were covered in blood. Thames and the crew were more than happy to keep the joke going and let her believe it was her fault.

“I remember afterwards, initially, everyone was like, ‘Nico’s nails have just hurt our boy. Nico’s just cut our favorite cast member.’ And I remember being like, oh my God, this is awful,” she says. “And then we watched it back, and you could see him bash his chin. Thank God. I would’ve felt really… I felt so bad when we thought it was me. And he was not letting it up. He thought it was so funny.”

Thames isn’t the only one who injured himself on set. Though her character, Astrid, is very comfortable wielding an ax, Parker says she is a bit… less so. “I did get hurt a couple nights just because the ax is quite big and I’m not necessarily the most coordinated person on the planet, and sometimes it would just get away from me,” she admits.

She recalls one time when Astrid is supposed to be inside a dragon’s mouth, knocking out its teeth with her weapon. “I was bashing away at teeth, and I hit one of them, and the ax bounced off the tooth, and whacked me in the face. And I remember standing there and just being like, this is so embarrassing,” she says, adding, “I was just getting battered all the time. I hit my hand on a pole. I just was constantly hurting myself. But nothing as bad as Mason getting stitches.”

Speaking of, Parker was all too happy to get a little innocent revenge on her costar and friend, telling us, “He also burnt his hand. Did he tell you that he burnt his hand as well? He was doing blacksmithing. I don’t even think we’d started filming yet, and he burnt his hand. He was a mess.”

As director, DeBlois spent most of his time watching monitors in a tent on set. But even he wasn’t immune to dragon danger. “I had avoided getting COVID all the way up until mid-production,” he says. “I had our script supervisor, our visual effects supervisor, and our cinematographer coming in [to the tent], and everybody had COVID, so I was sandwiched in there, and I could not avoid it.”

Once he had the disease, he says the crew set him up with “this little hazmat area,” his own “dedicated tent” — but nothing, not even COVID, could rain on his parade. “Honestly, I loved it. I loved every minute, even when it was cold and raining and even snowing at points, I was just giddy,” he says of his experience making the film. “People didn’t quite understand it, actually. I went into this thinking, this is either going to be the end of my career or maybe the start of a new direction in my career, but either way, I’m going to have a great time doing it, and so it’ll be an adventure.”

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His stars feel the same way. Thames says even the “horrible” double stitches were totally “worth it” in the end. And, even through all the teasing and axes to the face, Parker says she has nothing but “wonderful memories” from making the film. “I feel that definitely, as a set goes and a group of people and a cast and a crew and everything, I’ve never had a better time working ever. It really did feel like some of the best times of my life so far was working on that job,” she says.

How to Train Your Dragon, which also stars Gerard Butler, Nick Frost, Gabriel Howell, Julian Dennison, Bronwyn James, Harry Trevaldwyn, and Peter Serafinowicz, is now playing in theaters.

Gone but never forgotten: How to Train Your Dragon ends with a touching tribute to Gerard Butler’s late mom.

Audiences who stay through the very end of the credits for the film will see a note reading, “Dedicated to the loving memory of Margaret Coll.” The Scottish actor’s mother passed away in February at 81, according to PEOPLE.

Butler, who voiced the character of Viking Chief Stoick in the animated films and reprised the part in the new live-action remake, opened up about the surprise dedication in a new interview with UK-based radio station Magic Radio.

“I was so excited for her to see it, but I had a feeling she wasn’t going to make it. So Dean very kindly dedicated the movie to her,” Butler said, referring to writer-director Dean DeBlois.

“If Stoick had a mum, that would have been my mum,” Butler added. “She was an amazing woman, but she was strong, she was fiery, and she was graceful, and she was beautiful.”

The film, like the original 2010 animated hit of the same name, follows outcast Viking teen Hiccup (Mason Thames), who discovers he’s not like everyone else and cannot kill the dragons inhabiting the isle of Berk. He comes into his own and changes the fates of both Berk and dragons forever when he befriends one instead — the Night Fury Toothless — and learns their true ways.

Butler also opened up about why the film is so special to him, namely, that he relates to Hiccup’s story — though his mom was more supportive than Stoick is of his son’s interests.

“She wrote me the most beautiful letter, and she said, ‘Look son, end of the day, I want you to be happy, and I love you no matter what. And if this is what you want to do —'” he said, adding that she knew since Butler “was a kid” that he “wanted to be an actor.”

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“It’s this movie — it really is,” he continued. “But it’s the opposite, because I was doing something that I never really loved [before acting], never cared about, that didn’t show any of my uniqueness, and anyway to be honest, I felt that something else was going on, and she embraced that.”

For his part, DeBlois told The Hollywood Reporter that he wanted to surprise Butler with the dedication in the film.

“I knew that the loss of his mother was a deeply felt wound and that he was having a tough time recovering from it,” DeBlois said. “So to honor her with a dedication in the credits just seemed like the right thing to do in that moment.”

How to Train Your Dragon, which also stars Nico Parker, Nick Frost, Gabriel Howell, Julian Dennison, Bronwyn James, Harry Trevaldwyn, and Peter Serafinowicz, hits theaters Friday.