The Hulk has been on the big screen nearly half a dozen times, but Hollywood visual effects teams who are tasked with creating the biggest, strongest Avenger keep finding ways to reinvent the gamma-radiated wheel. For the Marvel Studios film, Thor: Ragnarok from director Taika Waititi, a very old approach to visual effects — scale models — was given a modern, 21st-century makeover.

Thor was literally punching above his weight during the God of Thunder’s gladiatorial brawl against the Hulk during the Grandmaster’s Contest of Champions. That created a bit of a problem for the movie’s VFX teams, because it’s trickier than you’d expect to make it look like a normal-sized man is really trading blows with a hulking giant. To pull it off, the film’s visual effects team, supervised by Jake Morrison of VFX outfit GOAT, used stunt actors whose substantial height difference matched the gap between Thor and the Hulk.

That means when you watch Thor: Ragnarok on Blu-ray (available now) and you see the 6-foot-3 Chris Hemsworth fight an 8-foot-6 CGI Hulk, you’re actually watching a 6-foot-4 Hulk stuntman fight Thor’s 4-foot-8 stand-in, British stuntman Paul Lowe, recognized as the “smallest stuntman on the British stunt registry.”

Morrison says solving for Hulk’s canon 8-foot-6 MCU height is tougher than fighting any gladiator. “He’s effectively impossible to do,” Morrison tells Inverse in a phone interview. For Thor: Ragnarok, the team wanted to avoid making Thor fighting Hulk “just another CGI creature” slugging it out like in every movie. “What we were trying to make it feel like was, if you had two dogs in a bar brawl, what would it be like?”

Thor's fight with the Hulk used human "scale models" to produce a sequence that was realistic as possible. British stuntman Paul Lowe, who stands 4'8", filled in as Thor for shooting.

First, the filmmakers designed the Grandmaster’s arena without distractions, so Hulk and Thor fight in an open field. “There’s no windows to throw people, no furniture to jump over. It’s just the two in a sand pit. You smash people into walls, but really, it’s god against god,” Morrison says. He adds that the issue with creating the fight solely with computers doesn’t account for “that physical interaction,” which had the Ragnarok team “racking our brains.”

Morrison’s not lacking in experience. He’s worked on other Marvel films, like 2012’s The Avengers, which also had a fight between the Hulk and Thor, albeit smaller in scale. “The only time Thor and Hulk fought was in the Helicarrier,” he says. “We built a big Hulk arm on crutches, big foam arms, so when Chris had to grab, Chris would hold that. But someone was puppeteering.”

In other shots for The Avengers, the filmmakers had a 6-foot-7 stuntman wear a shoulder rig that would raise his height to Hulk’s real size, but “You can still tell the punches are being thrown from a guy that’s 6-foot-7.” His punches gave it away. “The angles of the punch comes from where your shoulders are.”

Morrison then hit upon the idea of approaching the scene like scaled miniatures. “It’s been what we’ve been using in visual effects since cinema started,” he says. “If you can’t get an 8-foot-6 stunt guy, we can get somebody 6-foot-4. Scale that down, you end up with Thor being 4-foot-8.”

Finding a 6-foot-4 stuntman for the Hulk was easy. But for Thor, the filmmakers cast Lowe, whose stature and boxer’s build has him frequently working as a double in films like Batman Begins (he was young Bruce Wayne), TV’s Game of Thrones, and the Harry Potter series. “Now we’ve got the same physical relationship between Hulk and Thor. They could actually train and choreograph a scale version of the fight.”

Paul Lowe, who played Thor in the gladiator match of 'Thor: Ragnarok.'

The modern spin was taking their fight and combining with motion capture for the Hulk and compositing shots of Chris Hemsworth, who learned Paul Lowe’s choreography move for move and shot it in front of a blue screen. Morrison calls the process like putting together a jigsaw puzzle, “and they all fit.”

“It feels much more realistic than we would have gotten any other way,” he says. “We started from a place of reality but also fantasy.”

Thor: Ragnarok is available now on Blu-ray.