Army of the Dead's official trailer teases a different race of zombies than mainstream audiences are used to, but it turns out that certain species are immune to the plague.

Director Zack Snyder named which species would be safe from the outbreak during a Q&A with Netflix. "The only creatures immune from the zombie virus are birds," Snyder said.

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He continued, "You know, birds have their own paths, and we tend not to try and get too much into their heads because you know, they're birds." He added, "But yeah, that was the one thing that we decided in our science because you know, it is science, that birds would be immune."

The director also revealed that the undead tiger was always a part of his vision for the film, stating, "Yeah, we really liked the idea of the tiger." He added, "I really thought it was cool. And that he would play, you know, sort of, he's a bit of a MacGuffin, he tends to show up and kind of change things, you know, a little bit."

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The Justice League director also promised to fans that the Army of the Dead anime series will feature a variety of zombie animals, noting, "There'll be horses and dogs. And I mean, we don't have dogs in the movie. In the animated prequel that we're working on, there are a lot of zombie dogs."

Directed and co-written by Zack Snyder, Army of the Dead stars Dave Bautista, Garret Dillahunt, Ella Purnell, Omari Hardwick, Raul Castillo, Tig Notaro, Theo Rossi and Ana de la Reguera. The film arrives on Netflix May 21.

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Source: Netflix