Will Blake is the villainous werewolf from The Werewolf of Fever Swamp, the 14th book from the Goosebumps series, as well as the Goosebumps episode under the same title.
Will lived in Fever Swamp and served as a friend of main protagonist Grady Tucker, who moved with his family to the small town. Grady had learned about a werewolf prowling around Fever Swamp at night, killing various animals and even a hunter, though Cassie's statements were disputed by Will, who stated that he didn't believe in such things. When various dead animals were recently found in the area, Grady's pet dog, Wolf, was accused, but Grady began believing the claims of a werewolf roaming Fever Swamp.
Grady theorized that the eccentric Swamp Hermit was the werewolf, but he had to prove it before his father planned to put down Wolf, due to his belief that he was responsible for the killings. Later that evening, with the full moon in the night sky, Grady encountered Will while he was looking for Wolf, who ran off some time prior. Will turned heel and transformed into a werewolf under the full moon, and it was shortly afterwards that he attacked Grady, who quickly recognized Will due to the facial features. Will bit Grady during the attack, but was run off by Wolf; however, Grady ended up receiving the curse and became a werewolf at the end of the novel, now taking over Fever Swamp after Will's disappearance.
The TV version featured numerous differences, with one of them being that Will actually believed in werewolves, and stated that the Swamp Hermit was the werewolf terrorizing Fever Swamp. Just like the novel, Grady believes this as well, but the claim is disproven when the werewolf--who had went after Grady's mother and sister--was caught in the Hermit's net. The Hermit expressed joy over his capture, as the werewolf killed his family. However, the werewolf broke free and killed the Hermit, and continued his pursuit of Grady.
Will's reveal as the werewolf also differed from the novel, as the TV version had Will's heel persona uncovered when the moon's eclipse revealed his partial human form. Will urged Grady to run off before he transforms again, due to having formed a friendship with Grady; however, Will began turning heel again when the moon's visibility steadily increased, as he began compulsively howling while attempting to control his evil side. Once the full moon returned to its complete form, the evil Will transformed into a werewolf and later went after Grady. At that moment, Wolf appeared and fought off Will by sending him sinking into the bog and to his demise.
Despite everything that happen, Grady begin to feel sorry for him before leaving. His Skeleton is then seen rising out of the quicksand.