I know everyone's already said about the campaign.

I didn’t mind what 343 gave us for a story at all and I think Halo 5 is a great game, but I do think with just a few tweaks to missions/ different missions or different cutscens we could have had the epic hunt advertised. Here’s just my take on what could have been done even with what already exists mostly. Sorry for any grammar mistakes.

Osiris:
Spartan Throne is in Osiris instead of Buck, when Jul’ and Halsey are found Locke prepares to engage Jul’ but, Throne jumps the gun and fights the Elite instead resulting in the escape of Jul’ and the near death of Throne with Locke barely saving the wounded Spartan.

Blue Team:
Blue Team successfully beings to purge the files off of ONI’s database on Argent Moon however Chief see’s files pertaining to Cortana and has a hard copy made of select files pertaining to Cortana being potentially alive, this disallows further file purge and Blue Team is force to blow the station, specifically against orders and returns to Infinity. Osiris has returned when Blue Team get’s back and Locke is talking to a few Spartans in Helljumper armor looking for a replacement among them. Palmer questions Chief’s disobeying of orders and his downloads, Chief attacks Palmer when the subject shifts to Cortana, Locke intervenes and assaults Chief as Blue Team defend themselves from the Spartan Four’s. Chief ends the fight by throwing Locke off a railing and has Blue team retreat to a hanger where they steal a Prowler and go to the last known blip of Cortana, Meridian.

Glassed:
Locke recover’s quickly as Blue Team leave and passes Palmer who gives permission to pursue and arrest Blue Team, Locke hastily grabs the Spartan Buck as his replacement member in a rush and they board a Pelican and set their course to follow Blue Team.

Meridian Station:
Blue Team lands on Meridian and is greeted by hostile human colonials, they fight through the colonials and are soon trapped by a Governor Sloan, with human forces surrounding the Spartan’s and a new contact slipping in from slipspace the Spartans are assessing, when Prometheans appear and attack the colonials then lock Sloan out of some systems allowing them to escape with their newfound allies, the mission ends as Blue Team moves towards a underground structure.

Unconfirmed:
Osiris lands and takes the elevator down to find the colony in chaos and a Governor ready to kill them, Locke explains they are there to hunt the rogue Spartans and the Governor points them the way Blue Team when and sends reinforcements to assist their progress through the Promethean assault, they encounter the Warden after entering the underground structure and defeat him then proceed to engage Blue Team, Vale and Tanaka struggle against Kelly and Linda while Buck, Fred, Locke and Chief trade blows, Vale and Tanaka go down and the rest of Osiris is ganged by Blue Team who activates a console before disappearing, claiming they have jobs to do. The Guardian begins to activate and Osiris retreat away back towards the Colony.

Evacuation:
Osiris runs to escape the effects of the Guardian and leave Meridian, with Locke gaining permission to go to the place where one known unactivated Guardian still exists, Sanghelios. Locke radios Palmer to meet him there with Doctor Halsey.

Reunion:
Blue Team arrives on Genesis and with Promethean support, assault and destroy Covenant and Human forces brought in by the Guardians recent arrive, they are talked to by the Warden who helps them clear a path to activate consoles which will bring more Guardians. Chief and the Warden also talk about the new master of the domain, Cortana who will see him soon, Blue Team is directed to move in her direction.

Swords of Sanghelios:
Osiris tracks the location of the Arbiter and pinpoints him, fighting through Covenant forces and meeting up with the Swords of Sanghelios, then proceeding to save the Arbiter’s life. The Swords agree by the Arbiter’s word not to kill the team despite running into the middle of a civil war in a zone the UNSC shouldn’t be.

Alliance:
Locke explains the need to activate the Guardian to the Arbiter, explaining the need to put down Blue Team to which the Arbiter remarks “were it so easy, if demons were as easy to kill as you make out, we’d have killed them long ago”, the Arbiter also explains the Guardian is in the last city held by the Covenant on Sanghelios, but tells Locke if he help’s the Swords assault a strongpoint nearby he’ll get them into the city.

Enemy Lines:
Osiris assists the Swords and pushes the Covenant out of the strongpoint, killing a Kraken. A call comes out from the Swords base, they are under attack by Prometheans.

Before the Storm:
Osiris and the Swords fight the Prometheans in their base and destroy them, a Warden appears and is put down by a combined effort. The Arbiter gives the signal to all Swords of Sanghelios, Sunaion will fall today. In the distance the rumbles of the Guardian begin.

Battle of Sunaion:
The Swords, Arbiter and Osiris cut through the city decimating all in their path. The Arbiter breaks off to follow a lead on Jul’. Osiris arrive at the Guardian and use Palmer’s Pelican to board the Guardian hoping it will take them where Blue Team went. The Arbiter is seen dragging the body of Jul’ and claiming victory over the Covenant. The Swords begin to retreat as the Guardians shockwaves tear apart the city.

Genesis:
Osiris arrives on Genesis and track Blue Team to a relay point. They find a friendly Monitor and are attacked by the Warden. The monitor claims it can teleport them close to where the last Reclaimers were and they leave.

The Breaking:
Blue Team moves to finally reunite will Cortana yet due to the sudden arrival of Osiris nearby the Warden turns on them and uses his Prometheans to attempt to try and stop both teams. They both race to reach the top first, with Blue Team reaching a large strange room. The monitor disappears and Osiris arrive and open fire on Blue Team with Locke calling Chief a traitor to his own kind. The Warden and Cortana appear and the Warden is ordered to kill Osiris and summons hundreds of bodies to attacks. Osiris fights and loses, yet the Monitor appears and teleports them out of harms way, Blue Team talks to Cortana and is betrayed by her.

Guardians:
The Monitor and Osiris race to prevent Cortana from leaving with Blue Team, they succeed and Cortana loses Blue Team as she jumps out of system. Blue Team emerges and calls a truce with Osiris realizing Cortana’s mad plan and the need to stop her at any cost. Knowing they can’t return to human space due to the threat of Cortana and her created, they reunite with the Arbiter, his Swords and a wounded Palmer with Doctor Halsey. The rest plays out basically the same except during the Legendary ending you hear Cortana’s voice and the voice of the Diadect. (Yes I know the Diadect is supposed to be dead)

> 2533274849820175;1:
> Osiris:
> Spartan Throne is in Osiris instead of Buck, when Jul’ and Halsey are found Locke prepares to engage Jul’ but, Throne jumps the gun and fights the Elite instead resulting in the escape of Jul’ and the near death of Throne with Locke barely saving the wounded Spartan.

Thorne actually was planned to be in Osiris instead of Buck. The only reason why that plan changed is because Ethan Peck, Thorne’s voice actor, wasn’t available.

Of course, even earlier in development, Osiris wasn’t going to be in the game at all, and it was going to be Fireteam Majestic instead.