Prell also works as an animator with Valve. Outside of her works on shows, Prell has made public appearances performing Red Fraggle, like appearances at Comic. Demonstrating that her affection for the Muppets has not waned, however, Prell attended MuppetFest in , resplendent in a homemade Red Fraggle cap, and also. Prell currently works as an animator with Valve Corporation. Outside of her works on shows, Prell has made public appearances performing Red Fraggle, like. PRELL: Well, from what I understand yeah, they really had it working well but it still took a lot of work to do for five years and they were all ready for a. Karen puppeteered and voiced film and television Muppet characters for 16 years, living and working in New York, Toronto and London. Karen Leigh Prell (born J) is an American puppeteer and Outside of her works on shows, Prell has made public appearances. Valve Animator Karen Prell talks about her early career as a Jim Henson To learn more about Prell's work, head to From working as a puppeteer on Fraggle Rock to animating characters for the award-winning video game Portal 2, Karen Prell has had a long. Gundowringa ;: The life and work of Charles Ernest Prell [Bayley, William Alan] on *FREE* shipping on qualifying offers. Gundowringa ;: The life. As a teenage Muppet fan I bombarded Henson Associates with fan letters and inquiries about puppet building or performing work.