The Walking Dead is well-known for its harrowing zombie-focused storytelling that constantly puts its characters through the wringer, with an alien invasion being a farfetched idea that series creator Robert Kirkman has only jokingly mentioned being a plausible possibility. But in a new piece of non-canon bonus content, extraterrestrials have invaded the post-apocalyptic world of The Walking Dead, showing fans exactly what aliens would have looked like had they become an official part of Rick Grimes’ constant struggle to survive.