Zack Snyder has reveled there's more than one type of zombie in his Netflix movie, Army of the Dead.

Snyder broke down the different categories of zombies in a live Q&A following the Army of the Dead trailer premiere. "[We] have two categories of zombies in the movie, alphas and then normal shamblers," he explained. "[If] you see a zombie movie, normal shamblers, it's like a normal zombie, they kind of move slowly. And then our alphas, which are an evolved version of zombies and zombies that have taken another step, and they're much... they're fast, and we kind of treat them kind of like almost like wolves or like, they're not... they're sentient, you know what I mean? They kind of, they fight [in] packs and they kind of have a pack mentality."

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Army of the Dead takes place in a world where Las Vegas has been laid to ruin by a zombie plague, prompting the U.S. government to quarantine the city by erecting a massive wall around it. The film then follows a group of mercenaries who venture into Vegas in the hopes of breaking in and stealing millions of dollars from one of the city's abandoned casinos. The Army of the Dead trailer shows the movie's human characters encountering the countless zombies that now reside within the city's limits, bringing them face to face with a literal army of alpha zombies in the process.

In addition to featuring different categories of zombies, Army of the Dead will include what Snyder has described as a "very deep dive with the why of the zombie plague and where it starts." This will also lay the groundwork for a greater franchise that includes an untitled prequel movie directed by and starring Army of the Dead actor Matthias Schweighöfer, along with an anime series titled Army of the Dead: Lost Vegas. Both of those projects are already moving forward, with Snyder hinting at the possibility of an Army of the Dead sequel, should the first film prove successful enough to warrant it.

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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