Gears 5 is the most narratively ambitious Gears of War game to date. It expects the player to be following the new story that began in Gears of War 4, but since that came out years ago, chances are many players don't remember the fine details of that game.

The new Gears of War game is out today for Game Pass Ultimate subscribers and next Tuesday for everyone else. Gears 5 continues the iconic apocalyptic third-person shooter franchise, best known for its chainsaw guns and cover system.

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Gears 5 starts players off with a friendly "what you missed on Gears 4" intro that's pretty helpful. But if players are jumping in fresh without any context, or just want a more detailed explanation here is exactly what happened in Gears of War 4 and why it's important to Gears 5. 

Gears of War 4 begins on the 25th anniversary of the end of the Locust war. The player character is JD Fenix, Marcus's now adult son. JD leads a crew of Outsiders, a faction in opposition to the COG who are now oppressive government types. The Outsider crew that stars as the group protagonist of the game consists of JD, best friend Del, Kait Diaz, and her uncle Oscar.

The four are breaking into a COG settlement under construction to steal a fabricator. They are confronted by DeeBees, automated robots who serve as a main enemy type in the new games. This makes First Minister Jinn angry at them, accusing the Outsiders of "taking her people" in relation to recent disappearances of COGs. When hearing of Jinn's anger back at the village, Kait's mom Reyna is not a happy camper either.

Overnight, a swarm of Locust-like creatures invade the village and takes the villagers, leaving only JD, Del, and Kait. After JD cuts a crystal from a severed Swarm hand, Del suggests taking it to JD's estranged father, Marcus Fenix. Marucs is not too happy to leave his tomatoes behind, but leads them to a place where they can find more crystals after narrowly avoiding capture by Jinn's Deebees.

The Outsiders discover that the Swarm was harvesting people, explaining the disappearances. Soon after, Marcus is abducted by a giant Swarm creature called the Snatcher. Fighting through heavy Swarm resistance they find and kill the Snatcher, saving Marcus, who has seen some things. Marcus tells the team that while inside the pod, he was connected to the Swarm's network. He confirmed that, yes, the Locust had never fully died out but became stronger Scions who now lead the Swarm army and are using humans to create more Swarm. Marcus then informs Kait that the Swarm is treating Reyna differently, and that she's being held at a burial site near a dam outside the city of Tollen.

As they battle to the top of the dam, Marcus suggests taking a detour to get backup from a "friend." This leads the team to a radio tower in the town of Speyer, where Marcus gets in contact with his friends — Baird and Cole returning in an all-time great Gears moment

Del, Marcus, Cole, and Baird board a King Raven, while leaving JD and Kait to pilot the mechs for the final assault on the dam. They break through the dam to find the Swarm hive. The largest Swarm creature yet emerges and takes down the helicopter.  JD is forced to kill it using the machine gun from the downed helicopter.

At the end of Gears of War 4, the squad enters the hive to find a Reyna and some revelations follow. Reyna is half-human, fused with the hive and says if she is disconnected that she would die; in fact she wants to die. Everyone leaves as Kait cuts her mother free free and grants her final wish, but before she does Reyna hands Kait her medallion. We see Kait emerge from the cavern. She says her mother told her the medallion belonged to her grandmother. When she turns it around for the final shot of the game, we see a Locust emblem.

On that cliffhanger, Gears of War 4 cut to credits but isn't quite over yet. In a post-credits scene Oscar, who is presumed dead, escapes from a dead Snatcher. Presumably setting up that Oscar will have a much larger role in Gears 5. Which makes sense, given that we now know how much of the game focuses on Kait.

The campaign of Gears 5 continues this emotional rollercoaster in the dramatically changed campaign mode.

Gears 5 launches on September 10 for PC and Xbox One.

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