On Wednesday, it was announced that The Walking Dead: The Alien, written by Brian K. Vaughan and drawn by artist Marcos Martin, was released exclusively digital on Panel Syndicate, where you can pay whatever you want to download it. Below is the cover of the comic and watch the video below with Robert Kirkman and Brian K. Vaughan to hear how this comic came about. Read more about it on thewalkingdead.com. Robert Kirkman has said that it is canon.