Warner Bros. has trademarked several titles for the upcoming Man of Steel 2, which is tentatively titled Batman vs. Superman.

Though an official title for Man of Steel 2 has not yet been decided, Fusible has discovered a series of titles that Warner Bros. registered as possible titles for the highly anticipated film.

All of the titles are variations on Man of Steel: [Subtitle], similar to Marvel's strategy, which uses titles like Thor: The Dark World and Captain America: The Winter Soldier.

Here is a list of possible titles registered by Warner Bros.:

Man of Steel: Battle the Knight

Man of Steel: Beyond Darkness

Man of Steel: Black of Knight

Man of Steel: Darkness Falls

Man of Steel: Knight Falls

Man of Steel: Shadow of the Night

Man of Steel: The Blackest Hour

Man of Steel: The Darkness Within

Each of these titles emphasizes the night and darkness in some way, indicating that the film will be darker in tone. Warner Bros. also registered shortened titles, such as Battle the Knight, Black of Knight, Knight Falls and The Blackest Hour. Considering Batman is commonly known as "The Dark Knight," it can be assumed that the film will focus significantly on the iconic superhero.

Batman Controlling Drones in Man of Steel 2

In Man of Steel 2, Batman (Ben Affleck) and Superman (Henry Cavill) will be facing off in several physical conflicts, hence the tentative title of Batman vs. Superman. However, Superman's nemesis Lex Luthor will also be in the film, and he will likely be the main villain.

Lex Luthor Different Than Usual for Batman vs. Superman Film? 

Man of Steel 2 is scheduled for release in theaters on July 17, 2015.