San Diego Comic-Con 2013 is a day away, and rumors have spread like wildfire across the Internet, like casting for Marvel's Doctor Strange, possible surprise appearances, and what "secrets" will be revealed in Hall H.

As a result, MTV complied a list of what Comic-Con rumors they have reportedly found to be true, including the confirmation of a Metallica appearance:

Nobody at Comic-Con wants to keep a secret that secret because then none of the attendees will ever hear about it. That's why you end up with several not-so-secret surprises in the days and weeks before the event. This year, the big non-surprise belongs to Metallica. The metal band is scheduled for a Hall H appearance to promote their concert movie "Through the Never," which stars Dane DeHaan in the film's narrative segments, but a press release also went out about a "secret" concert weeks before Comic-Con even started.

According to reports, Joseph Gordon Levitt is rumored to be Marvel's favorited to play Stephen Strange, a neurologist who becomes Earth's mightiest magician after an accident leaves him unable to perform surgery. 

There are also reports that 20th Century Fox will hold a huge panel at the convention center for its "X-Men: Days of Future Past" cast, which includes Hugh Jackman, Michael Fassbender, James McAvoy and Halle Berry.

Others are excited for the first look into the upcoming young-adult films "Divergent" and "Ender's Game."

"Ender's Game" is the sci-fi adaptation of the Orson Scott Card novel, starring "Hugo" lead Asa Butterfield as the alien-fighting hero.  The film also feature "Star Wars" legend Harrison Ford.

"Divergent" takes place in a future civilization divided into five factions that are devoted to positive human attributes: Candor (the honest), Amity (the peaceful), Erudite (the smart), Abnegation (the selfless), and Dauntless (the brave).  The story follows protagonist Tris (Shaleine Woodly) who discovers she's Divergent, someone who can be placed in multiple factions, but doesn't necessarily want to be one.

Click here for a list of movie panels you should definitely attend during your Comic-Con 2013 visit. To see the schedule for the convention, click here.