As Finger says, "You never see a dinosaur swinging by its tail." (The tail is one of the monster's stronger physical traits, capable of grabbing people and allowing it to latch on to structures and hang in midair.)
Other touchstones in creating the monster including walruses, crocodiles, and paraplegics were less predictable. Footage of paraplegics in motion, for example, was useful because Bong and the Orphanage's creation has just two legs at the very front of its long body. Though incredibly graceful in water, it is challenged on land, where it has a baby's unpredictable sense of balance. "There is a shot when [it] is first kind of rampaging around in this park area along the Han River, and [it] stumbles and basically does a face-plant and kicks up some dust," Spaw says. "It's great, really engaging the audience to believe that this thing is not perfect."
To create the CGI version of the monster, the Orphanage relied on a small clay model, or maquette, sculpted by the New Zealand F/X house Weta Digital (King Kong and the Lord of the Rings trilogy), which was constructed using a design that Bong commissioned from artist Chin Wei-chen. Bong had wanted the creature to be completely CGI, but when Rafferty realized there would be significant close-ups involving live actors and the creature, he petitioned for a live puppet as well.
Consequently, the Australian company John Cox Creature Workshop constructed a two-ton model of the beast's head, a particularly complex piece of art. While the head as a whole resembles a nasty fish, the open mouth is bizarre and unique, as if a vagina had sprouted leathery butterfly wings adorned with spikes. The Orphanage had to adapt its animation to the Cox model, ensuring that the digital monster's movements and characteristics matched those of the puppet. "We had to cater the animation process, which we normally don't do like how the creature's mouth opens and closes," Kulig says. "The mouth alone had so many intricate parts."
One possible reason for The Host's success is that the Orphanage and Bong's South Korean crew routinely defied convention throughout their collaboration. "It was amazing to watch how Director Bong's mind worked," Kulig says. "He would react to CGI footage we already had and shoot all these shots that weren't on the schedule. None of us could figure out what he was doing. But when we showed up the next day and saw the footage edited, it worked beautifully."
Constantly interacting with the Orphanage representatives on set, Bong also recorded daily videos for the SF team in which he critiqued footage projected on a wall behind him. He was adamant that the creature look ungainly and act awkwardly like, as Kulig puts it, a "fish out of water." Both despite and because of its clumsiness, the creature wreaks considerable havoc on the residents of Seoul and, in particular, a few of the film's main characters. In some cases the violence proved too great to use actual people. For these shots the Orphanage employed what it calls "digital doubles," or animated versions of the actors. But whenever possible Bong used his cast, who gamely submitted to a variety of miserable scenarios, including being pummeled by cushion-wielding men (stand-ins for the creature) and getting repeatedly dragged through the Han River.
As the South Korean film industry's cachet has risen worldwide, coproductions with other countries have become more commonplace. The Host, the first major F/X film in Korean history, is also the first to employ a company with strong ties to Hollywood. Finger, Kulig, and Spaw describe an on-set camaraderie in which everyone was both intensely hardworking and jovial. "The opportunity to work with pretty much the most famous Korean actors out there was amazing," Finger says.