We can thank a Jim Henson Company puppeteer for some of Valve's best animation work

While Deadlock's sort-of-launch last year was proof that Valve does, in fact, still make videogames, its immaculate vibes served as a different sort of reminder: That the studio remains among the best in the business of characterful animation. From Meet the Heavy's moments of tender minigun affection to the cyclopean gesticulation of Portal 2's Wheatley, Valve's artists and animators are masters at the subtle craft of imbuing even virtual and inhuman characters with humanity.

Which is why it felt fitting to learn that Valve's house style has Muppet DNA in the mix, thanks to a Jim Henson Company puppeteer that helped the studio bring its characters to life.

I learned about Valve's rainbow connection while doing a regular reappraisal of the studio's lore, as all professional writers on the PC games beat are dutybound to perform. In Geoff Keighley's The Final Hours of Portal 2, an interactive book about the project's closing stages and its developers that was originally released for the iPad in 2011, there's a moment where the nascent Game Awards magnate mentions the presence of "the puppeteer who played the character of Red Fraggle on the 1980s television show Fraggle Rock."

That puppeteer, I soon learned, was Karen Prell. Prell was hired to work at the Jim Henson Company in 1979 at the age of 20, after Muppets creator Jim Henson had watched an audition tape that Prell had made while still a teenager. Henson was impressed enough to invite her to audition for the Company in person in New York City, where she was hired the same day.

During her tenure of working and performing alongside globally-recognized innovators in the crafts of puppetry, animatronics, and practical effects at the company, Prell was asked by Henson in 1982 to puppet Red Fraggle, one of the show's central—and eventually, one of its most popular—characters, when she was just 22. In 1986, she achieved puppetry apotheosis in Henson's Labyrinth, where she was the puppeteer of the worm.

In 1997, Prell entered what she calls on her website her "second career" by entering employment at yet another landmark institution of the visual arts: She signed on as an animator at Pixar, working on films like A Bug's Life, Toy Story 2, and Geri's Game—that delightful short of the old man playing chess, which just warped my brain backwards in time by two decades simply by being remembered.

Career number three came for Prell in 2007, when she was convinced by her animator peers and friends to interview at Valve despite never having played a videogame in her life. As you might expect from a studio given the chance to hire someone who boasts experience as both a Jim Henson Company puppeteer and a Pixar animator, Valve didn't pass on the opportunity.

Prell's earliest work at the studio was as an animator and playtester on Left 4 Dead, during which, Keighley writes, "the younger Valve employees got quite a kick out of hearing Karen scream expletives after a Boomer zombie had spit vision-impairing bile on her screen." From there, she'd continue to have a hand in some of Valve's most beloved games, contributing concepting and animation for TF2 and its Meet the Team shorts, in-game animations and mocap cleanup for Left 4 Dead 2, and—her crowning achievement at Valve—Portal 2's Wheatley.

"Wheatley was designed, modelled and rigged by Richard Lord before I tackled his acting," Prell writes on her website. "Wheatley’s animation process involved creating an extensive and intricately planned library of reusable movement and acting components that could be rapidly composited together to create unique actions for each of his hundreds of lines of dialogue. Wheatley’s acting, movements and timing were heavily influenced by the stylized acting I employed while performing hand puppets."

As Wheatley's animator, Prell did the impossible: She bestowed life on an orb. With all his carefully crafted squints, dilations, and emphatic plate flexing, Wheatley manages to seem more lively and emotive in 2011 than some humanoid characters are today. I mean, look at Kliff Crimsondesert. Guy barely seems to register that he's alive. And if that wasn't enough, she also contributed animation work for the co-op bots and GladOS, assisted with localization, and even pitched in on Portal 2 apparel and merchandising design.

After appearing in the credits of Counter-Strike: Global Offensive, Artifact, Half-Life: Alyx, the latest Valve release that lists Prell's name is 2022's Aperture Desk Job. After making an indelible mark on the studio's visual language, she returned to career number one, reprising her role as Red Fraggle for Apple TV's 2022 reboot of Fraggle Rock.

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