 The characters guest-starred in the 1999 "Rugrats" episode #106 "Ghost Story".Before that, David Eccles, the voice of Krumm, provided the monster voice coming from under Chuckie's bed.Josef Adalian of "The Washington Times" praised the show's animation and sense of humor, although it was not as "hip and witty" as "The Ren & Stimpy Show" or "The Simpsons".