Note: No leaked content was viewed in the creation of this post.
I’ve collected every picture, concept art, and information in general about the campaign that I could, in order to piece together what will happen in Halo 4’s campaign in a general sense. I tried to provide links to pictures that backed up everything that isn’t just pure speculation, but unfortunately I did not have enough characters left to do this. I can provide any pictures or logic that I used in a reply if requested. Please keep in mind that this is mostly speculation.
Opening Cutscene:
Halo 4 will have an opening cutscene mission, similar to Halo 3 and Reach. It will give an introduction to the Halo franchise for new players.
First Mission: Dawn
The UNSC Forward Unto Dawn is adrift in space. Inside Master Chief is still in cryo, and has been for nearly 5 years. Cortana wakes Chief because something is boarding them. Not long after Chief wakes up, FUD gets scanned by Requiem/the Didact. Chief climbs up an elevator shaft, which isn’t pressurized, dodging falling debris along the way. He gets to the top, only to be attacked by an Elite. He pushes the Elite down the shaft and continues on towards the observation deck. Once he gets there he finds out about he Covenant fleet, but then more Storm troops board FUD through the observation deck’s windows. Chief makes his way outside, to FUD’s weapons systems. He activates them and destroys a Storm cruiser, then Requiem opens and starts sucking anything nearby inside. Chief travels back inside, but eventually FUD tears itself apart and Chief is forced into a controlled free-fall towards the planet. When he lands he uses a piece of the wreckage that he grabbed on to during his free-fall as cover as wreckage rains down on him.
Second Mission: Requiem
Once everything is safe, Chief emerges from the wreckage. He finds a Warthog that has survived the crash and uses it to get as far way from the crash site as possible, as Storm will be looking for him. This mission is focused mainly on exploring Requiem, but there will be skirmishes as Storm has found out that you are not at the crash site and are sweeping the area. Chief eventually takes cover inside a Forerunner structure filled with Sentinels. Cortana hacks into the system and we learn a lot more about Requiem, and its purpose. Cortana receives a transmission from Infinity saying that they are on their way, but can’t respond due to interference caused by Requiem. The two know how dangerous Requiem is and wish to stop Infinity from approaching the planet. They move deeper into the structure, eventually stumbling upon a large room with a terminal in the middle. Cortana accesses the terminal, and uses it to track the interference to the core of Requiem, which is essentially another, smaller, planet within the inner planet Chief is already on. Not long after the Prometheans show up, and Cortana and Chief quickly vacate the room.
Third Mission: Forerunner
Cortana opens a portal using the systems in the Forerunner structure. This leads Chief to an observation deck of sorts, which overlooks the entire area. As you’re trying to get to the first pylon the Prometheans attack you. They are trying to defend Requiem. Storm is in chaos, none of them have any idea how to deal with this new, deadly, threat. You get to both pylons and shut them down. Chief’s transponder isn’t powerful enough to transmit the message, and Infinity is getting extremely close to entering the planet. Cortana opens another portal, which leads to another observation deck. From there she opens yet another portal, which leads to a relay outpost, which, unknowing to Chief and Cortana, holds the Didact’s Cryptum, hence Storm’s interest in the location. Chief accidentally wakes the Didact from his slumber, and is attacked by the Forerunner. The Didact then gains control of the Prometheans and forms an alliance with Storm.
Fourth Mission: Infinity
The Didact was able to take control of Infinity before they could get away. Infinity crash lands in the jungle on Requiem. Chief rendezvous with UNSC forces and they find their way to a number of crashed ships in order to collect IFF tags. When they finish they return to Infinity. Once they make it back Chief gets in a Mantis and is instructed to help clear Infinity of Storm and the Prometheans. Chief them climbs in the Mantis and proceeds to fight off the Covenant. Once he gets to the outer deck, Chief uses either Infinity’s guns or his Mantis to fire at the Didact’s Cryptum, which causes him to flee. Once this is done he meets with Captain Del Rino, the captain of Infinity. This meeting is essential, and much is explained during it. Though the captain wishes to leave, Chief and Cortana eventually convince him to stay.
Fifth Mission: Reclaimer
Infinity may have gotten off the ground, but it isn’t completely free quite yet. A nearby gravity well generator, which is being controlled by the Didact, is keeping them from going anywhere. Chief and other UNSC forces, which include Mammoths, launch an assault to destroy the generator. Along the way the encounter a large weapon, which is eventually destroyed using the Mammoth’s main gun. The UNSC forces then continue to the generator, and also destroy that using the Mammoth’s main gun. All forces return to Infinity, which then pursues the Didact in an effort to stop him.
Sixth Mission: Shutdown
Infinity has tracked the Didact to a mountainous region of Requiem, which is home to many pillars which hang from the ceiling. Chief uses a Pelican Gunship to attack the Didact and the forces that are aiding him. At some point Chief is forces out of his Pelican and on to the Didact’s Cryptum, and proceeds to nearly fall, despite his efforts to save himself. Fortunately he lands on either a Covenant or UNSC flying vehicle, and boards it. Unfortunately he fails to stop the Didact, who has been developing a plan to get off of Requiem.
Seventh Mission: Composer
The Didact has not only successfully found a way off of Requiem, he has also gained access to a number of Forerunner ships. With these ships in his possession he makes for Installation 07, a UNSC controlled Halo and the home of the Composer, which the Didact wishes to use to expand his army. Infinity, who is in pursuit, has informed the UNSC, who is amassing a fleet there in an attempt to stop him. Among these ships is the ship from Primordium, where ONI is questioning Chakas about the Didact in order to learn as much as they can about him. The battle has already begun as the Didact has arrived. Chakas gives them no answers, but instead takes control of the ship and leaves to find the Librarian. He informs the Librarian of the Didact’s escape, and she sets off to help stop him. She meets with Chief, and tells him many things, including information on the Prometheans and the Composer, as well as the Precursor’s “test”. She then gives him a “cure” to Halo’s effect, which she developed in the waning days of the Forerunner empire during her time on Earth.
Eight Mission: Midnight
The Didact eventually gains access to the Halo and fires a controlled burst at the remainder of the fleet. Fortunately, thanks to the Librarian, Chief survives. He then hunts down the Didact and successfully stops him, with the help of Cortana.