Ever since director Zack Snyder revealed that the Man of Steel 2 sequel will feature fellow superhero Batman, the rumor mill on who will play the Gotham City superhero for the DC Comics film have been rampant.

The latest casting rumor is that Christian Bale will reprise his role as Bruce Wayne in the upcoming Superman vs Batman flick. The actor was reportedly offered $50 million to take up the role, according to publishers of Beyond Batman: The Unauthorized True Story of Christian Bale and His Dark Knight Dilemma by Vince Russel.

In the book's summary, Russel writes: "Christian Bale's experience as the Batman of our generation is about to prove more inescapable than he expected. With three of the most successful Batman films in Hollywood history under his belt, Christian Bale is now facing extraordinary pressure to become The Dark Knight once more."

The actor and Warner Bros. have not made any comment on this new rumor.

Other contenders on the rumor mill for the role include Tyler Hoechlin, Ryan Gosling, Joseph Gordon Levitt, Michael Fassbender, Jake Gyllenhaal and Chris Pine.

There is no confirmation that villain Lex Luthor will make it into the big screen in the upcoming sequel. He did not appear in Man of Steel but if he does appear in the next film, the latest casting rumors for the part of the villain is Bryan Cranston. The actor has appeared in Argo, Godzilla and Netflix's House of Cards. Another strong contender is Mark Strong.

Nonetheless, the Batman vs Superman / Superman vs Batman /Man of Steel 2 movie will not be released until 2015 and production is set to begin early 2014.