Some reviewers found the underlying concepts to be clever, such as a "Wired" review that opined the film had a "clever premise," "outrageous characters, some artsy scenery, and some cool laboratories. "The Sydney Morning Herald" praised it for being unique from most family films due to its cast of improv actors and impertinent horror concept: ""Igor" celebrates a defiantly adolescent and suitably caricatured vision of mortality with the potential to have adults and special young malcontents in stitches." A "Total Film" reviewer called it "a compellingly oddball tale that should eventually find its niche as a minor late-night cult classic for "Nightmare Before Christmas" fans," although called its themes of "suicide and spousal abuse" odd for a family film. Some critics called it one of the rare family flicks to appeal to adults as well as kids. In the words of a "Newsday" character, "the overall tenor of "Igor" is goofily funny — probably a bit sophisticated for kids but certainly good-natured," and "the animated characters possess an unusual depth of emotion." "The A.V. Club" labeled it an "appealing mix of macabre, reference-heavy horror-movie trappings and good-natured positivism," favorably comparing it to Burton's works for being "appealingly manic and cute as well as sick." A five-out-of-five review from "Dread Central" claimed, "The comedic timing is top notch with humor that is 95% mean spirited, often remarkably dark and at times even a little gory." Even a reviewer who found the film's concept conformist, Peter Bradshaw, wrote that it was made up for by its dark tone.