Back 4 Blood is one of this fall's most anticipated games, as it looks to give players the exhilaration of slaying hordes of zombies. In the latest Back 4 Blood trailer, it is explained just where the zombies came from.

Back 4 Blood is an upcoming co-op first-person shooter where players must fight for survival against the undead known as the Ridden. Reminiscent of Left 4 Dead, Back 4 Blood puts its own spin on the 4-player-team gameplay, with multiple characters for players to choose from, each with their own special abilities and traits. Whether it's being up close and personal with the zombies or shooting them from afar, every character plays differently. Over 4.6 million players participated in the Back 4 Blood beta, an indication of just how excited fans are to get their hands on the game.

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Turtle Rock Studios uploaded a new campaign trailer for Back 4 Blood revealing the origin of the game's zombies. The first half of the trailer is narrated by the character of Phillips, also known as General, with the trailer being framed as if he is recounting the world's story to the rest of the cast. Phillips explains that it was a tiny, parasitic worm "whose emergence was buried beneath the mountain of politics," that caused the outbreak. From that point, people who were immune to the virus, the Cleaners, took up the fight against the Ridden, but it may just be too much for them, with how many different zombies are in Back 4 Blood.

The trailer also teases what the game's story might entail. A line by Phillips following his narration indicates that he is adamant about pressing some sort of advantage against the Ridden, although it is unclear what that advantage is. Shortly after, the character of Mom expresses her agreement with Phillips, that they are in a war against the Ridden, not before implying that she does not think very highly of him. Considering just how massive Back 4 Blood's zombie hordes look, the story seems like one of desperation, of trying to win and unwinnable fight.

What is perhaps most interesting about the trailer is Phillips line about the origin of the Ridden worm: "buried beanth the mountain of politics." The statement may somewhat detail the worm's origin, as it conveys some sort of governmental, political cover up, but it more so characterizes Phillips as someone who may be anti-politics. Since Back 4 Blood will have ongoing content after launch, maybe the answers will come further down the line. Either way, it seems like a solid setup for what is to be a very exciting game.

Back 4 Blood releases on October 12, 2021, for PC, PS4, PS5, Xbox One, and Xbox Series X/S.

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