Almost since the beginning of movies, people have been trying to use the medium to conjure up fantastic creatures. From Godzilla to Gremlins, there’s nothing like a hideous monster or a furry freak of nature to inspire fear and glee in the audience. The artists, technicians, and designers who create these beasts are highly talented, highly specialized—and highly imaginative. Mental Floss spoke to a few for some insight into the fanciful world of monster making.

1. CREATURE EFFECTS HAVE COME A LONG WAY SINCE GUYS IN RUBBER SUITS.

Bruno Vincent/Getty Images

The earliest creature features typically involved a guy in a rubber suit terrorizing Tokyo or carrying off a damsel in distress. Today’s creatures are much more complex and believable, thanks to new varieties of silicone rubber, upgrades in animatronics, new forms of design software, and the development of CGI.

“Special Effects as an industry is always evolving, and products and materials are expanding and becoming more readily available than ever before,” says Stuart Rowsell, a creature technician and founder of Bloodhound FX in Australia who has worked on films including Star Wars: Episode II (2002) and III (2005), Superman Returns (2006), Mad Max: Fury Road (2015), and Alien: Covenant (2017).

3D printing is also shaking up the industry. Lino Stavole, a creature engineer at Spectral Motion based in Los Angeles, founded 3D scanning, printing, and engineering company Behold 3D to cater to the needs of the entertainment industry. Stavole tells Mental Floss that his company used 3D printing in silicone to create an alien creature for the movie V/H/S in just two days, a process that once required several more. “That really opened my eyes to the potential of what technology can do,” he says. 3D printing is also pushing boundaries in terms of design intricacy—Stavole says a creature he helped create for Netflix’s planned reboot of Lost in Space incorporates about 400 different 3D-printed parts.

2. BUT SOMETIMES, THE CREATURE IS STILL A GUY IN A RUBBER SUIT.

Technological advances have by no means pushed the classic creature suit aside, however—particularly when enhanced with a little digital magic or combined with other techniques like puppetry. A suit offers certain advantages over digital or animatronic creations, after all: “Fluidity of movement is usually why the guy in the suit is required,” Rowsell tells Mental Floss. “They can run through corridors, crawl through water, caves, tunnels, and react in close quarter fighting with characters. Often it is a lot easier to make a creature suit than it is to make an animatronic puppet.”

3. A SINGLE CREATURE OFTEN REQUIRES MANY DR. FRANKENSTEINS.

A 3D-printed model made by Behold 3D from the film Ender's Game (2013) for Amalgamated Dynamics Inc. Lino Stavole

Bringing a creature to life is a big job, one usually beyond the capacity of any single designer or artisan. The traditional skills involved include concept design, body casting, sculpting, molding, and painting, while more modern skills like computer animation, digital design, and engineering now round out the list. The broad array of skills required means that making a creature is typically a team effort—and participants tend to specialize. “A lot of people think you’re going to be building a creature from design to completion, but that’s not normally the case. It’s very faceted,” Stavole says.

Of course, some creature artists are the full package. Rowsell says he’s never specialized, and being competent in both design and the various aspects of fabrication has allowed him greater control over the final product. “My business relies on mostly myself,” he says, “so I have quality control and I only have myself to blame if it goes wrong!”

4. THE BEST CREATURE DESIGNERS HAVE TWO BRAINS.

Regardless of specialty, the best creature artists are typically those who are able to think in two different ways. Stavole compares the two mindsets to aliens living on two different planets. “You have an alien on one planet who is like a Vulcan,” he says, “and Vulcans like science, so this brain of a creature designer knows about anatomy, physiology, biology, entomology, and physics—that is the science part of creature design.” The other planet is populated by artistic types. “They communicate with pictures and sculptures, but they also have to communicate history and character with creature design,” he says. Stavole explains that, as a natural Vulcan, he works to help the artists and designers on a creature team understand which sorts of structures will help their design move more naturally.

Given these differing approaches, communication is key. Stavole says he has a deep respect for specialists, but adds “the people who have a more complete overview of things tend to be the best communicators and have the best results.”

5. ONE CREATURE MIGHT ACTUALLY BE MANY CREATURES.

A "wheelbarrow" version of one of the giant lizards made by John Cox Creature Workshop for the 1999 film KomodoStuart Rowsell

It’s a fact of movie magic that a creature presented as a single entity on screen may actually consist of several different versions used in tandem to create the illusion of life. Rowsell explains that while working on the 1999 movie Komodo with John Cox Creature Workshop, the creature crew made several versions of the giant lizards that appear in the film, including full-size animatronic- and puppeteer-driven komodos, as well as both full-length and wheelbarrow-style (i.e. just the front half on a wheelbarrow rig) creatures. A fully CGI lizard was also created “for the wide shots of the komodo’s faster and deadlier action," Roswell adds.

The luxury of having many creatures to work with, however, is very dependent on budget. Stavole points out that some productions will try to make one version of a creature work throughout a film, because it’s more cost-effective.

6. EVEN KING KONG HAS TO STICK TO A BUDGET.

And yes, even fantastical creatures have money problems. “The creature effect on any feature film or commercial depends on the budget. Usually the production company wants 10 thousand dollars to look like one million dollars,” Rowsell says. Budget is often the determining factor in whether a creature is rendered entirely practically (i.e. in physical materials), entirely digitally, or a combination of the two. It also influences details like whether a production can afford to pay a day rate for a puppeteer to manipulate elements like tails or wings—which often gives a more natural feel than rendering those elements digitally. “It is essentially our job to make as convincing as possible an original-looking creature within the deadlines and budget that performs on-set without falling to pieces,” Rowsell explains.

7. THEIR CREATIONS ARE INSPIRED BY REAL LIFE.

A prop for the 2003 movie Peter Pan, made by John Cox Creature Workshop (Foam Latex Supervisor Stuart Rowsell)Stuart Rowsell

When it comes to the design process that precedes any crafting or building, creature artists draw inspiration from the natural world. They study animal and plant life, and borrow elements of bone structure, skin texture, and physical movement. (Interestingly, Rowsell worked in an abattoir before becoming a full-time artist, where he got a crash course in anatomy and internal organs. He says he recalled the horrible things he saw there when designing the innards of the lizards on Komodo).

They must also take into account another earthly presence: the director. “The director’s vision is paramount to any film,” Rowsell explains. And while the designers may draw on a broad array of sources and render hundreds of drawings of a creature, it is the director who makes the final call when it comes to design.

8. … AND SOMETIMES BY VISITS TO THE MORGUE.

Creature design does involve anatomy, but the morgues designers rely on don't house bodies. In this case, “morgue” refers to a collection of images and ephemera, long a mainstay of artist repertoires and newspaper industry archives.

Stavole, who considers himself to be more of a creature engineer or artisan than a designer, says that when he does take on design, he likes to work with a morgue. For him, this means doing a search of libraries and the internet for images, consulting with various people for ideas, and throwing everything he finds into a sort of creative stew. From that stew, surprises can emerge. “Happy accidents can happen and ideas from one project can get incorporated into another project,” he says.

9. MANY OF THE BEST CREATURES ARE PART PRACTICAL AND PART DIGITAL.

While advances in digital technology have changed the movie creature landscape, they’re unlikely to eliminate the need for practical effects and many traditional techniques any time soon. “Many SPFX artists were worried in the early '90s that CGI would end the industry,” Rowsell says, “but CGI has been very good to the special effects industry. It has enhanced it.”

According to Rowsell, working with practical creature effects comes with a host of considerations: foam rubber creatures or suits can tear or break down under wear; they can lack realism; and unlike a purely digital creation, they cannot be completely changed in post-production. But CGI can seem fake or end up looking like a video game. “I can still see (CGI) as a flat animation from a mile away,” he says, “whereas practical effects have substance.” The ideal situation, then, is a bit of both worlds: practical elements to add substance and weight, and CGI elements to augment the effect. “Today’s creature effects, when they work best,” Rowsell adds, “are 50% practical and 50% CGI-enhanced.”