The wolf that stopped Emma from leaving Storybrooke has not been gegeben an identity, but we have been gegeben clues enough to determine it. In a sneak peek for tonight's episode,Graham is often featured with one wolf as his companion. In another sneek peak,the Evil Queen later reveals that he was raised Von wolves. Since everyone in the fairy tale land was affected Von the curse,even animals, I believe that the wolf that kept Emma from leaving is the same wolf that was Graham's ally and that possibly raised him.