In the last article, we covered the Post-War Era that followed the events of Halo 3, in which the UNSC rearmed itself significantly, and the galaxy attempted to find a way to reach peace despite civil wars and territorial disputes.

Complete Halo timeline series

In this one, we're going to go over the events of Halo 4, in which the Master Chief returns — and accidentally releases an ancient enemy that he has to defeat when he finds himself situated on a Forerunner world never seen by the UNSC. For this article, I highly recommend reading through the first and second timeline articles again, as the information within them is essential to grasp in order to understand the events that occur in this one.

July 21, 2557 CE (Current Era): Cortana wakes up the Master Chief

Conceptual artwork for Halo 4.

Almost five entire years after Master Chief and Cortana were left adrift in space on the UNSC frigate Forward Unto Dawn following the defeat of The Flood at The Ark, the ship's intruder alarm systems were triggered. Cortana, shocked by this, immediately woke up Master Chief from his cryo-sleep and alerted him to the situation. As the intruder systems warned that the enemy force was spreading throughout the vessel, Master Chief began to conduct a search of the ship. As he did so, he was attacked by a Sangheili energy swordsman. After killing him, Chief asked Cortana why Covenant forces were attacking a UNSC vessel despite the end of the war, but she didn't have an answer. As Chief encountered more Covenant troops, he noticed that they appeared different compared to enemies he had faced before; this was due to the fact that they were a remnant faction of Covenant soldiers who had decided not to ally with the Arbiter during the Post-War years.

As Chief continued to clear the ship, Cortana informed him that a nearby Covenant cruiser was moving closer to the Forward Unto Dawn in order to attack it. However, it had its shields down, and missiles would be able to destroy it. Unfortunately, the Forward Unto Dawns' weapons systems were malfunctioning, so Master Chief had to manually fire the explosives by going on the outside of the ship's hull. The Covenant attempted to stop him from doing so, but were ultimately unsuccessful; the missile barrage that ensued tore into the vulnerable Covenant cruiser and destroyed it. While he was out there, Chief noticed that the Forward Unto Dawn was drifting towards what looked like a metal Forerunner planet.

The gravity well of the mysterious planet pulled in both the Forward Unto Dawn and the Covenant fleet attacking it.

Though this moment was a victory for Master Chief and Cortana, it wouldn't last. Right after the destruction of the Covenant cruiser, the planet began to scan Master Chief. Once it identified him as a Reclaimer, a large hole opened in the shell of the planet, and a gravity-well began to pull in everything in orbit, including both the Covenant ships and the Forward Unto Dawn. Master Chief attempted to reach an escape pod to get away, but he was unable to do so. He was ultimately knocked unconscious when he hit a piece of debris at high speed as he was sucked into the planet's opening.

The Didact is awoken, and the UNSC Infinity arrives

Master Chief and Cortana look upon the core of Requiem.

After waking up from his crash-landing, Master Chief and Cortana attempted to figure out what to do next. After seeing and hearing Cortana begin to lose control of herself and say random phrases, Cortana revealed to him that she was becoming rampant, which is when an AI breaks down after seven years of service. Cortana had been active for eight, so her condition was worsening fast. Chief theorized that since Catherine Halsey made Cortana, she could fix her; thus, his primary objective became figuring out a way to get off of the mysterious Forerunner planet and back home.

As Chief fought off attacks from Covenant forces that had survived the crash-landing, Cortana tried to make a distress call to the UNSC. However, their transmission was mysteriously being jammed. As Chief and Cortana began searching for a way to disable the jamming, they ended up learning that the planet was called Requiem and that it was constructed in layers. The metal shell was the first layer, the "normal" landmasses and oceans underneath was the second layer, and the final layer was a hollow center. This is where the jamming signal was coming from. As Master Chief traveled to the innermost layer, he was attacked by Promethean warriors that the Didact had created eons ago. They attacked the Covenant as well, and a chaotic three-way battle between Chief, the Covenant, and the Prometheans ensued. During the fighting, Cortana picked up on a faint signal from the UNSC Infinity, which was on a mission to discover new Forerunner locations. Cortana urged Chief to hurry and disable the jamming so that she could contact the ship and warn it of the gravity well.

The Didact's telekinetic powers enabled him to prevent Master Chief from moving.

Eventually, Master Chief disabled the two pylons that were causing the communication interference. Unfortunately, these same pylons were also what was holding the Didact imprisoned within his Cryptum. After the Didact awoke, he quickly declares that he is going to ensure Forerunner ascendancy once again and takes control of his Prometheans directly, who were up until this point fighting passively. He reveals his hatred for humanity (this is due to his long and troubled past) and vows to prevent them from obtaining the Mantle of Responsibility. The Covenant present, who still view Forerunners as gods, swear their allegiance to the Didact, and he chooses to accept their help. Thankfully, Master Chief is able to narrowly escape the newly-allied Promethean and Covenant forces.

The UNSC Infinity ultimately was pulled into Requiem due to the gravity well, but since communications weren't jammed anymore, Chief was able to contact the vessel and head towards its crash site, helping Marines and Spartan-IVs defend the ship. Covenant forces were able to disable the ship's point defense systems with EMP devices, but after Chief destroys them, the ship is able to destroy two Covenant cruisers and even does enough damage to the Didact's Cryptum (which he began using as an armored transport vessel) to make him retreat. With some time to rest, Master Chief gets acquainted with the officers of the UNSC Infinity: Captain Andrew Del Rio, Commander Thomas Lasky, and Spartan-IV Commander Sarah Palmer.

The UNSC Infinity departs, as does the Didact

The crew of the Infinity sends a Mammoth vehicle to destroy the gravity well keeping the ship grounded.

The Librarian's genesong gave Master Chief the ability to survive the Composer.

Master Chief insists that it's critical to stop the Didact before he can leave Requiem, but Del Rio disagrees and orders him to join an assault force tasked with destroying the gravity well that's keeping the UNSC Infinity grounded. Lead by the massive Mammoth heavy vehicle that's equipped with a miniature MAC gun, the assault force is successfully able to destroy the gravity well. Suddenly, Master Chief is subjected to experiencing an illusion with a "personality imprint" of the Librarian, which is similar to an AI. The Librarian warns Chief of the Didact's plan to use the Composer, a device that can transform humans into Promethean soldiers, in order to wipe humanity out. Then, she gives him a special gene implant called a genesong, which enables him to survive the Composer's effects.

With the gravity well disabled, the Infinity is able to leave. Despite Master Chief's strong voice of concern, Del Rio dismisses the threat of the Didact and the Composer and orders that the Infinity return to Earth, leaving Chief with only a Pelican dropship. Chief attempts to use the Pelican to prevent the Didact from leaving Requiem, but this is unsuccessful; ultimately, the Didact goes aboard his massive flagship, the Mantle's Approach, and begins to travel to the Composer's location through slipspace, flanked by a fleet of Covenant ships. In order to pursue, Master Chief stows aboard one of these vessels.

July 24, 2557 CE: The Didact raids Ivanoff Station

Ivanoff Station was located on Installation 03, and was studying the Composer prior to the Didact's arrival.

After three days of slipspace travel, the Didact and his flotilla of Covenant allies arrived at Installation 03, one of the Halo arrays. Their target was Ivanoff Station, a UNSC research facility that was studying the Composer to figure out what it was for, as they had found it on the Halo ring. The Covenant quickly began blowing through the minimal security force there and started to overrun the station, slaughtering every scientist they found and disabling the station's automated defense systems. Master Chief and Cortana assist in the defense of the station and get the automated guns back online as they travel to the Composer with hopes of moving it or destroying it so that the Didact couldn't use it, but unfortunately, they were unable to do so.

The Didact was able to take control of the Composer, and before anyone had enough time to react, he used it on everyone still alive at Ivanoff Station, instantly killing every person in the facility and transmitting their essence to a storage location where they could be turned into Prometheans. Master Chief was knocked unconscious by the Composer, but thanks to the Librarian's genesong, he ultimately survived unharmed.

Realizing that the Didact now had everything he needed to assault Earth, Master Chief, and Cortana raced to get aboard a nearby UNSC Broadsword fighter and flew it underneath the shields of the Mantle's Approach as it entered slipspace and headed towards Earth. Their plan was to find a way aboard once there, taking the ship's nuclear payload with them, and detonating it manually from the inside, destroying the Mantle's Approach from the inside-out, as well as the Composer.

July 25, 2557 CE: Master Chief and Cortana defeat the Didact

The Didact and Master Chief engaging one another on a hard light bridge above the Composer.

The Mantle's Approach was more than a match for the UNSC fleet at Earth.

Upon arriving at Earth, the Mantle's Approach immediately began to attack nearby UNSC ships and defenses in order to get a clear shot at Earth for the Composer. The UNSC home defense forces retaliated with all of their might, but the attacks were ineffective against the ship's heavy Forerunner shielding. The UNSC Infinity had enough firepower to punch a hole in the hull if it could get closer and get a better shot, but the Mantle's Approach's defense guns were preventing that. After Master Chief made his presence known with a communication message, Commander Lasky (who was now the captain of the Infinity, as the UNSC had demoted Del Rio) asked if Chief could disable the guns preventing Infinity from effectively attacking. Since Chief was underneath the ship's shields, his fighter craft's weapons were effective in disabling the defenses. This allowed the Infinity to launch a heavy concentrated attack that created a small opening for Master Chief to enter the vessel with.

After making his way inside of the Mantle's Approach, Chief fought his way through hordes of Prometheans and eventually got close to where the Didact and the Composer were. Both of them were protected with thick shielding that would protect them from the nuclear blast, so Cortana devised a strategy to disable the shields; creating fragments of herself to spread throughout the ship, overloading the shield systems and failing them. As Cortana did this, Chief continued to battle his way towards the Didact.

While Cortana did manage to disable the shielding, the Composer had already started firing, and it was killing millions of humans in the city of New Phoenix down on Earth. The Didact, noticing Chief's intent with the nuclear bomb, used his telekinetic abilities to prevent him from activating it; however, Cortana's fragments created hard light shackles to restrain the Didact, freeing Chief from his control. Master Chief seized this opportunity, sticking the Didact with a grenade that wounded him and caused him to fall into the slipspace portal below that was being used to transport the essences of the humans being composed. Then, ready to face his death, Chief activated the nuclear warhead, destroying the Composer completely and ending the threat.

Cortana saves Master Chief

Though Chief thought he would be killed by manually detonating the nuke, he in fact survived; this is because Cortana used one of her fragments to teleport him away from the blast and shield him within a bubble of hard light. Cortana, confident that she can't be saved from her fate, says an emotional goodbye to Chief before seemingly passing away as all of her fragments go silent. Though the hard light bubble dissipates, a Pelican ship combing through the wreckage of the Composer finds Chief and brings him aboard.

In the days following the event, Master Chief contemplates the death of his friend as he prepares to reintegrate with the UNSC and face whatever threat comes next. Soon, he would be reunited with his family, the other Spartan-IIs of Blue Team: Fred-104, Kelly-087, and Linda-058.

Though the Didact was defeated, the Covenant was not done with the world of Requiem — and neither was the crew of the UNSC Infinity, who prepared to launch a second campaign on the Forerunner planet spearheaded by a daring force of Spartan-IVs...

Your thoughts

What do you think of the events of Halo 4? Personally, I love this game, and it's my second favorite title in the Halo series behind Halo 2. Let me know your opinion, and make sure to catch the next article when it's out!

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