Call of Duty: Black Ops Cold War Zombies has started a bold new chapter for Treyarch’s iconic co-op mode. With the original Aether story wrapping up in Call of Duty: Black Ops 4, the Dark Aether story continues the narrative with a brand-new cast. Only Samantha Maxis has returned thus far, and while Call of Duty: Black Ops Cold War could surprise fans with another returning character in the future, it may continue to forge its own path.

With Mauer Der Toten launching on July 15, fans are closing in on the next big chapter of the Dark Aether storyline. Through the various main quests and intel pieces, several plot threads have been set up, and it will be interesting to see which ones Treyarch unravels in this new map. For those that have not kept up with all the plot developments, or are simply looking for a refresher before Mauer Der Toten, here is everything that has happened in Call of Duty: Black Ops Cold War Zombies thus far.

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The Events Of Die Maschine In Call of Duty: Black Ops Cold War

Call Of Duty Black Ops Cold War Project Endstation

Die Maschine was the launch map for Call of Duty: Black Ops Cold War Zombies, and it did a fine job establishing the Dark Aether universe. Its intro cutscene saw the campaign character Weaver interacting with an older Samantha Maxis, with the latter warning the former about the return of the undead. A meaningful scene for two reasons, this cinematic confirmed that the campaign and Zombies universes are now connected while also revealing that Sam is the new story’s protagonist. As far as the map itself goes, it is centered around an old Nazi laboratory in Poland.

While seeing Nacht Der Untoten again is a nice bit of nostalgia for longtime players, the underground area housing Projekt Endstation is where the story plays out. Endstation was helmed by Dr. Vogel, a Nazi scientist tasked with creating atomic weaponry for the Third Reich. However, his particle accelerator malfunctioned and saw him opening the Dark Aether instead, a parallel dimension where Zombies and other monstrosities reside. While the Aetherium from the dimension did allow for some advanced technology, this element came with the cost of the Nazi’s lives. The base was quickly overrun by the undead and abandoned, though not before a large portion of the Nazi regime was able to hide away inside the Dark Aether.

While the Nazis hid inside the dark dimension, waiting to strike, Russia eventually found the remains of Projekt Endstation. Though they initially shut down the cyclotron and kept the undead locked away, Cold War paranoia saw it re-opened decades later. Now attempting to harness the power of the Dark Aether, a Russia-backed faction of scientists named the Omega Group has begun experimenting on the undead. Players learn of this backstory during the main quest, partnering with a reanimated member of Omega named Orlov to destroy the facility. While they do succeed in the lab's destruction, they are too late to stop Omega, as the group has begun experimenting with the Dark Aether in other parts of the world. One of these locations is Vietnam, the setting for Call of Duty: Black Ops Cold War’s second Survival map.

The Events Of Firebase Z In Call of Duty: Black Ops Cold War

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While players do head to Omega’s Vietnam base after Die Maschine, the mission is not to stop the enemy group. Instead, players need to rescue Samantha Maxis in Firebase Z's main quest, as the beloved Zombies character had been captured when trying to infiltrate the base. Players meet Ravenov and Dr. Peck early on, with the former being Sam’s contact in Omega and the latter being the man that captured her. Before long, Peck informs players that Samantha is trapped within the Dark Aether, locked away with no method of escape.

Given Sam’s importance to the narrative and her experience with fighting the undead, it is not too shocking that she was able to keep herself alive while stuck in the Dark Aether. Eventually, the main quest sees Weaver’s agents freeing Sam, with Requiem killing an Orda mini boss and escaping the map. After the main scene, Peck is punished for his failure by Kravchenko, another returning campaign character. While Kravchenko removes Peck’s eye, another Omega agent is revealed. Named Valentina, intel confirms that she is the daughter of Dr. Vogel, the Nazi scientist behind Projekt Endstation.

As a whole, Call of Duty Zombies intel began to get a lot more interesting around the time of Firebase Z. Players learn that The Stranger, a survivor trapped in the Dark Aether that has been communicating with the player, is actually named Zykov. Having been the one to turn off the cyclotron after the Russians found the Die Maschine lab, he has been stuck in the dimension since World War 2. Surviving largely due to a tamed Hellhound named Cinder, it will be interesting to see if he ever takes on a role outside of intel. The intel also teased a close relationship between Samantha, Weaver, and a deceased boy, with many theorizing that the unnamed boy was Richtofen. Recent intel has made this seem less likely, however, so it remains to be seen if or when Eddie will debut in this new story.

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The Events Of Outbreak In Call of Duty: Black Ops Cold War

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In the five months since Firebase Z released, Zombies fans have been able to explore the game’s Outbreak mode. An open world experience that has only grown better with time, it is an interesting experiment on the part of Treyarch. While the maps do re-use Fireteam locations from multiplayer, Treyarch has added plenty of intel pieces for players to find. Alongside some cheerful recordings focused on a pet dog Weaver got for Samantha, players have learned about a Requiem traitor and The One. In the case of the traitor, Carver seems like the most likely candidate for the role of turncoat. This is because he may be trying to put the Cold War aside so that The One can be stopped, as he has learned of the threat. As for The One itself, it is the entity in control of the Zombies, though little else is known about it thus far.

Alongside objectives that see players helping Requiem's scientists catch up in the Cold War, Outbreak offers two easter egg quests to complete. In the first, players assist Maxis and Ravenov as they destroy some of Omega’s Aether rockets, which could have infected any city in the world if left untouched. While the quest offers a special location and great gameplay, it does little to progress the narrative. Outbreak’s Season 4 quest, on the other hand, is the opposite. Though it is brief, its cliffhanger ending is a game changer, as it sees Kravchenko capturing Weaver’s Requiem agents. While there was already bad blood between the two, as Kravchenko removed Weaver’s eye in the first Black Ops campaign, this will likely only make their feud worse.

With the player-controlled Operators now captured, Mauer Der Toten’s trailer has confirmed that they will be doing Kravchenko’s bidding in the next map. Forced to complete Omega tasks to keep their pilot Raptor-1 alive, the agents’ main goal is to kill an Omega traitor. This is all-but-guaranteed to be Valentina, as intel has suggested that she will be freeing the Nazis that have been hidden away in the Dark Aether for so long. However, she is only doing so because she believes her father is telling her to. In reality, The One is speaking to Valentina, deceiving her by diguising its voice to resemble her dad’s. While Valentina may or may not succeed at bringing back the Nazi army, she will likely let The One free to wreak havoc on the real world.

Clearly, the Season 4 Reloaded Zombies map has a lot of things to resolve. While the Requiem traitor is likely Carver, this is unconfirmed, and a reveal will be interesting to see play out. Showing The One escaping could be an exciting way to tease future maps, while Zykov and his pet Cinder might take on a bigger role. Sam’s powers could come into the spotlight, as could the unclear fate of Richtofen. With mysteries like the demonic blue bunny also on the table, Mauer Der Toten has the chance to move the story forward in a major way.

Call of Duty: Black Ops Cold War is available now on PC, PS4, PS5, Xbox One, and Xbox Series X.

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