When all of a sudden he gets a visit by none other than Bruce himself. But then came the end credits scene. Another Telltale Batman season where I was helpless to save my friend from becoming a Batman villain. John, crestfallen in Arkham looks woefully at a picture of him and Bruce. The Joker is a minor character in Batman: The Telltale Series and a supporting character turned main antagonist in it's sequel Batman: The Enemy Within.A mysterious patient at Arkham Asylum known as "John Doe", Joker became an ally to Bruce Wayne while he was incarcerated at the asylum. The one that sealed the whole season for me.