It's not too much longer until the release of Horizon Forbidden West and the continuation of Aloy's story. From what's been revealed so far, the sequel seems to continue with some narrative elements from Horizon Zero Dawn, such as a corruption-like plague sweeping over the land and causing plants and other biomatter to rapidly decay. To understand what this could mean for the story of Horizon Forbidden West, it's crucial to know the full story of Horizon Zero Dawn.

[WARNING: Major spoilers for the entirety of Horizon Zero Dawn and the Frozen Wilds DLC]

This is no easy feat however. The story of Horizon Zero Dawn spans multiple centuries and manages to get pretty specific about people, events, and dates thanks to the various data-logs found throughout the game. Not only that, the playable events of Horizon Zero Dawn and its DLC expansion, Frozen Wilds, are expansive and have a lot of moving parts, such as political conflicts, cultural systems, and entire religions.

Related: Horizon Zero Dawn Complete Edition vs Regular: Everything That's New

Keeping track of all these parts of Horizon Zero Dawn's story can get confusing. While players don't need to know every fine detail, there is still a lot of crucial history and events to know in order to have a good understanding of this world. This breakdown of Horizon Zero Dawn's story, in chronological order, explains everything that players need to know in order to jump into the world of Horizon Forbidden West with confidence.

Before The Events Of Horizon Zero Dawn, Explained

A photo of the Faro Plague machines from Horizon Zero Dawn.

In the mid-21st century, Ted Faro set the events in motion that would lead to the extinction of the human race. Faro was the founder and CEO of Faro Automated Systems, famed for their achievements in A.I. and robotics. They would become most well-known for their Metal Gear Solid-like battle robots known as the Chariot line of "Peacekeepers." Faro personally oversaw their development and designed them to be heavily armed and operate like a swarm of insects.

In his hubris, Faro made the mistake of making the robots near unstoppable. All of them consumed biomatter for fuel, the colossal Horus-class titans were able to self-replicate exponentially, and yjey had an operating system so well-protected that it would take decades to penetrate. To make it even worse, Faro purposefully excluded any failsafes that could shut them down.

This immediately became a problem in late 2064 when a system-breaking "glitch" infected one of the swarms and made them unresponsive to commands. In his panic about not being able to shut the swarms down, Faro contacted roboticist, bioengineer, and former partner Dr. Elisobet Sobeck to find a solution. A day later, Sobeck reported that the swarm isn't just unresponsive to orders, they're completely independent. The swarm was already beginning to replicate and Sobeck knew it was already beyond containment and estimated that it would devour all the Earth’s organic matter in only 15 months.

Related: How To Beat All Creatures Easily in Horizon: Zero Dawn (Tips & Strategies)

The swarm became appropriately known as the Faro Plague. Sobeck knew that there was nothing they could do to stop it from destroying life on Earth, but she did have an idea that would allow life to be reborn: Project Zero Dawn. It centered around GAIA, an A.I. designed by Sobeck to terraform and repopulate the planet. To do this, GAIA was accompanied by various subordinate functions, such as APOLLO, who was tasked with giving the new humans the knowledge of their past and HADES, who was tasked with resetting the process if something ever went wrong.

An image of Dr. Elisabet Sobeck's hologram next to GAIA and her subordinate functions in Horizon Zero Dawn.

It wouldn't be long after the completion of Project Zero Dawn that the biosphere began to disappear. The extreme loss of flora and fauna began depleting oxygen levels and killing off life faster than Death Stranding's Timefall. In order to survive, humans either needed re-breathers or had to be held inside sealed facilities.

Sobeck, Faro, and the Alpha members of Project Zero Dawn sealed themselves inside one such facility, GAIA Prime. One of the latches malfunctioned however, which allowed GAIA’s operating signals to bleed out and reveal their presence to the Faro Plague. In her final act of heroism, Sobeck donned the shield weaver armor to manually close the hatch from the outside, knowing that she wouldn’t be able to re-enter.

Inside the facility, Faro’s mental state quickly deteriorated, likely due to his guilt. This led him to wipe out all of APOLLO’s archives as he became convinced that the future of humanity would be corrupted by the knowledge of their past. He called a meeting with the Alpha members and informed them of his actions via hologram. As they berated him in horror, Faro remotely vented the oxygen out of the room and suffocated them all. Faro presumably died of old age inside GAIA Prime.

Related: Where Horizon Forbidden West Takes Place In The Real World

It's estimated that all life, including marine life, went destroyed by 2068. The mass extinction of mankind and the biosphere rendered Earth toxic and sterile, the Faro Plague went dormant. All the while, GAIA had been trying to break through the plague's encryption and at some point in the 23rd century, she succeeded and shut them down permanently. Finally, in the 24th century, Project Zero Dawn activated and life returned to the planet.

The Story of Horizon Zero Dawn Explained

Horizon Zero Dawn Producer Responds

In Autumn of 3020, a signal of unknown origin reaches GAIA and causes her to lose control of her subordinates. HADES, now independent, attempted to take control of the terraforming system in order to fulfill his directive even though it had been a success. Unable to beat HADES on her own, GAIA sacrificed herself by detonating the GAIA Prime facility to destroy him and the terraforming system, but HADES survived by implanting himself in the computer core of a Horus-class titan. HADES, now immobilized, developed a plan to reactivate the Faro Plague and fulfill his desire to eradicate life in a permanently, but he needed help. He sent out a signal in hopes someone would come to his aid, and a wanderer named Sylens did just that.

They began working together in exchange for knowledge of the old and new world. Sylens learned of the Old Ones and their downfall while HADES learned about the ongoing civil war between two powerful factions: the Carja and extremist Shadow Carja. Sylens introduced leaders of the Shadow Carja to HADES, who presented himself as one of their deities, the Buried Shadow. By manipulating their zealousness, HADES transformed the group in the Eclipse cult. With no more use for Sylens, HADES ordered him to be killed but was unsuccessful.

A year later, a newborn girl was found by the High Matriarchs of the Nora tribe, laying on the alter of the All-Mother. One matriarch, Teersa, saw this child as a blessing while her counterparts felt she was a curse from the gods and wanted her dead, arguing that she was placed in the Sacred Mountain by a metal devil as she had no mother. The infant was ultimately allowed to live but was deemed an outcast by Nora law and was placed in the care of another outcast named Rost.

Related: What Horizon Forbidden West Should Improve From Horizon Zero Dawn

Rost named the child Aloy and would dedicate his life to raising her. One day, six years later, Aloy was harassed by a group of Nora children while picking berries and ran away in anger, eventually falling down a hole into to a ruin of the Old Ones. After getting her bearings, Aloy found an arrow shaped object called a Focus, which displayed information and knowledge right before her eyes. She used the Focus to escape the ruins and reunite with Rost.

As Aloy continued questioning why she was an outcast and what happened to her mother, Rost told her that the best way to find out was by winning the Proving. This event is the coming of age ritual for the Nora, where those who complete it become Braves and the one who wins receives a boon from the High Matriarchs. Rost trains Aloy to be a master hunter in hopes that, by winning, she would learn the truth about her past.

Aloy running with Rost in the forest in Horizon Zero Dawn.

When the day of the Proving finally arrives and the other Nora teenagers tried to keep her from winning through foul play, but Aloy overcame them and crossed the finish line first. However, before she could be officially named the winner, a mysterious group attacked and killed all of the new Braves except for Aloy. She managed to stay calm and avoid making mistakes during combat, which resulted in the attacker's defeat. Upon investigating their bodies, she discovered they all had Focuses, but was then attacked and immobilized by their leader, Helis, before she could make sense of it.

Thankfully, Rost arrives in time to save Aloy, but is fatally stabbed in the process. Helis prepares explosives and leaves them to die in the blast. Rost makes his way over to a half-conscious Aloy and, with his final words, tells her to survive and pushes her off the side of the mountain. As she falls, she looks up to see Rost disappear into the explosion.

Sometime later, Aloy jolts awake inside the Sacred Mountain, having been nursed back to health by Teersa. Knowing her desire to learn of her past, Teersa takes Aloy to the alter of the All-Mother, where she was found, and Aloy’s Focus activates. It begins communicating with the All-Mother, which is really a doorway to some kind of facility that won't open due to the corruption that’s affecting the land and its machines. More importantly, Aloy sees the face of someone who looks a lot like her.

Related: Horizon Forbidden West Will Improve Zero Dawn's Melee Combat

Determined to open the door and find out who the woman is, Aloy is anointed as a Seeker which gives her the ability to travel freely. Shortly after leaving Nora lands for the first time, Aloy encounters corrupted machines that are aggressive and difficult to beat - some of which are entirely new to her. Aloy’s first goal is to track down a man she met the night before the Proving. He had a Focus like the attackers and was acting suspicious, and Aloy remembered that he was accompanied by Erend, a leader from Meridian. After traversing through some of the game's most breathtaking locations, Aloy finds Erend and learns that the person she’s looking for is named Olin. After investigating his home, they discovered that he is working with the group that attacked the Proving.

Aloy tracks Olin down to an excavation site and where the attackers are uncovering and reactivating ancient machines, known as Corrupters. Suddenly, their Focuses malfunction thanks to a mysterious voice that tells Aloy what she needs to do to take them down. She manages to eliminate the attackers and beat the Corrupters, leaving only her and Olin. Olin reveals that they are members of the Eclipse that serve an entity called HADES and that he was working with them to keep his kidnapped family alive. One of his jobs involved going to the Proving ceremony where they would look through his Focus to determine the best time to attack.

Horizon Zero Dawn's Story and Ending Explained

However, when the Eclipse saw Aloy through Olin's Focus, HADES made killing her a primary objective of the assault. Since Helis didn't stick around, they assumed Aloy died in the explosion - but this didn't last long. Aloy asked Olin about the woman she saw and he remembered seeing her image at a location known as Maker’s End. As Aloy makes her way there, she fights another group of Eclipse and the corrupted machines they controlled, thus alerting HADES that she still lives.

She manages to enter Maker’s End and discovers that it was once the headquarters of Faro Automated Solutions. Aloy also discovers that the identity of the woman is someone named Elizabet Sobeck and that she engineered something called Project Zero Dawn. Before leaving, the voice reveals himself to be Sylens. He directs Aloy to a place called the Grave-Hoard and eventually to the Zero Dawn facility hidden beneath the Shadow Carja capital, Sunfall. Though Aloy doesn’t fully trust him, she takes his advice and heads to the locations.

Related: Horizon Forbidden West Locations Marked Out On Real World Map

In the Grave-Hoard, Aloy comes across something called Operation: Enduring Victory, which she learns more about in the Zero Dawn facility. Operation: Enduring Victory was publicly portrayed as an attempt to fight back against the Faro Plague with some kind of overpowered CoD level super weapon, but in reality was an attempt to buy Sobeck enough time to finish Project Zero Dawn. Exploring further, Aloy enters a hologram theatre in which a projection of Sobeck plays, explaining Project Zero Dawn and all the functions of GAIA and her subordinates. Aloy, still unsure of her connection to Sobeck, investigates her office and finds copies of the Alpha Registry which would be able to open the door in the Sacred Mountain. Before she could leave, Aloy was incapacitated by Helis.

She comes to in a cage dangling above the grounds of a colosseum called the Sun-Ring. Helis taunts Aloy by crushing her Focus and dropping her down to the ground to face a Behemoth without her weapons. Aloy manages to use the machine's size to bring down various support columns to get her best weapons and finally take it down. Helis then sends out 2 Corrupters in retaliation, but before a battle could ensue Sylens breaks into the Sun-Ring with overridden Striders and escapes with Aloy. Once safe, he gives her a new focus with all of her old data backed up on it, including the Alpha registry. Aloy returns to the Sacred Mountain and opens the door to a facility called ELEUTHIA 9, where the new humans were raised until the food ran out and they were sent into the wild.

Horizon Zero Dawn's Story and Ending Explained

Aloy discovers the final recorded message from GAIA, where she learns that HADES can be defeated with the Master Override located in GAIA Prime. Most importantly, Aloy finally learns how she and Sobeck are connected. Though Aloy had come to hope Sobeck was her mother, GAIA reveals that she is a clone of Sobeck that was created when HADES went rogue with the hope that her intelligence would one day bring him down.

Aloy, unsure of how to process this information, sets her sights on GAIA Prime to retrieve the Master Override. She climbs the cold and bitter summit to reach the entrance to the facility. Here, Aloy learns the fate of the Alphas, Faro, and Sobeck. She retrieves the Master Override and leaves GAIA Prime, determined to not let their deaths be in vain. Aloy makes her way to Sylen’s workshop where he fashions the Master Override on to the tip of his lance. Before giving her the upgraded lance however, Sylens tells her the truth about how he brought HADES and the Eclipse to life and how he wishes to redeem himself by helping Aloy take them down. With that, he tells Aloy to confront HADES at a data tower known as The Spire, where he plans to broadcast the activation signal to bring back the dormant Faro Plague.

Related: What Horizon Zero Dawn's Villain Is Doing In Forbidden West

Aloy and her allies join one another at an outpost overlooking the Spire, ready to face off with the army of Eclipse. Together, they manage to defeat Helis, the Eclipse, and Aloy impales the Horus computer core, putting an end to HADES. With HADES deactivated, the corruption of the machines stopped and the Faro Plague remained dormant - but while everyone celebrated their victory, Aloy left for what was once known as Nevada. She arrives at the home of Elizabet Sobeck, where her body lies in a triangle of flowers. Aloy approaches and gently touches her helmet, revealing a hologram of her face. Aloy takes the locket that was hanging from her neck and holds on to it as she sits silently with Sobeck.

The Ending Of Horizon Zero Dawn Explained

Horizon Zero Dawn's Story and Ending Explained

After the credits of Horizon Zero Dawn, a group of scavengers are shown examining the impaled core that was once home to HADES. As they examined it, HADES’ essence shot out of the core and flew across the sky. It’s revealed that he was being summoned by Sylens, who traps HADES in some kind of container. In a sinister tone, Sylens tells HADES that they still have things to discuss as he walks towards to corpse of a Horus-class titan.

At the end of the DLC expansion, Horizon Zero Dawn: Frozen Wilds, one of GAIA's subordinates called HEPHAESTUS is building an army of new and highly dangerous machines made to kill. This revelation, as well as Sylens holding HADES, only indicate a future with more conflict and possible second extinction. Now caught up with the story of Horizon Zero Dawn so far, players are ready to jump into Horizon Forbidden West and continue Aloy's journey.

Next: Horizon Forbidden West Not Delayed Out Of 2021, Says Guerrilla