Note: I know the creator likely has their own ideas for these two levels. But thought I could put my hat in the ring just for a thought experement.

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PIllar of autumn

Start: The cutscene starts like normal but the Autumn is not alone two frigates flank her and several long swords and pelicans are seen in space.

The scene goes like normal up to the combat alert, you see more troops moving through the ship and armed pelicans (digsite) moving to positions. when johnson starts his speech there are more marines, the hog in the background has a few more following it.

Then as the player is woken they will find other pods opening with marines getting out in the black trooper suit. the tutorial will be skipped like a normal post tutorial start. though as the covenant breach the door and kill sam the other door opens and rocket fire kills the covenant, marines moving across one moving to check him.

At this point the game moves like normal up to the armory where you see more marines wounded, and several marines gearing up. loading rocket launchers, shotguns, and even a marine with the digsite needler minigun (recomend player start seeing it at 343)

Keys gives the player the magnum like normal after getting to the bridge. the next major change is around the corner litterally the three grunts are not there, instead they are piled in a corner while a marine looks at them shotgun in hand. he points you to the armory where you can get ammo for the pistol.

The player then heads into the armory, where they get not only ammo for the pistol but an Ma5 or a hidden Ma5GL. then an explosion is heard as the canteen is breached. the player is ordered to help the marines moving into the room to see several marines opening fire on covenant from the far side, the door across from the player explodes as elites pore in, across several grunts start running in with plasma pistols charging (green grunts) showing the covenant are really here in force.

The player continues to push with their objective being the escape pods like normal. the first boarding action happens with two marines dying and other marines opening fire. the mission shows marines holding the autumn more easily then in vanilla halo. the next major change coming to the room where you see the covenant shooting down escape pods, the door ahead is closed forcing you to watch, other marines are there having been holding out against the covenant from earlier.

as you watch the landing craft explode a tick approaches and latches to the far airlock a marine says "crap incoming boarders" as the doors open and you can move forward. The covenant poring out of the airlock and another. tick latching but a marine heading to the control panel saying "eat this." as they break the door causing an "explosive decompression" of the tick that just latched on killing all covenant inside.

a golden elite dying in the process. the mission then goes into the side passages, marines following you as you move to the room with the busted door, only to find it is currently a make shift med bay the door obviously having been busted on purpose. many wounded marines are there, as well as the players first weapon spawn for the standard shotgun. Sadly the weapon isn't really seen again till 343 but it is perfect for CQB maps. Along with that is two marines with the Ma5/GL version from digsite. these will follow you through the rest of the level. their launcher giving some good fire support.

As you move on you will find the cryo rooms, inside you will see a golden elite strike down a marine who will look up at you point and two camo elites will open fire finding the glass shielded as the elite moves down through the lower door.

Moving on you will hear over the radio that a support frigate has gone down, all crew are to abandon stations. This is when you get the order to move to the escape pods, there is no keeping the Autumn a float so to speak.

The player moving to the escape pods where instead of just one guarded by covenant you see marines escorting crew and wounded into the other two which launch just as you get there. the cutscene plays with in the back ground the golden elite approaching just as the shuttle launches. The custcene ends like normal.

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HALO
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The mission starts like normal airbreak failure and all, but instead of being alone the two Ma5GL marines survive along with a few others. one of the marines saying something like "evacs in the next valley we need to move."

The player and marines then make their way up the hill, several pelicans seen flying over an armed pelican shooting down one of them causing them to crash in the valley behind you.

at the choke point where you run into jackals for the first time is also a new enemy, an elite in dark blue armor who uses the charging version of the plasma rifle, its charge fire firing high explosive lobs of plasma while its standard fire is semi auto. it will try and stay behind the jackal shield wall, though y our allies can easily take them out with grenades.

moving into the valley you see a pelican taking off as marines fight off several covenant forces approaching from your side. The standard its a mess down here line is played as more covenant drop ships come in.

The big difference is during this fight you have marines with RPGs firing from the tower, the second spirit is even "shot down" sending it crashing into the valley before it can drop its troops. as you hold the ground eventaully foe hammer will come in, and land only for more life pods to launch. "I thought we where the last." "Those must be from the Frigates." "this isn't good." lines heard from marines.

Foe hammer looses her hog like normal and a marine gets on the passenger seat with a rocket launcher the player driving.


The mission goes like normal as you move into the cave and up to the split area, only this time the side the player is on has covenant setting up defenses you even see a spirit drop a shade turret before vanishing into the void. thankfully you have an ally with a rocket launcher clearing this side and activating the bridge you will see several grunts try to cross it as you activate it along with a ghost. though as it activates and you regain control you will see your hog drive off across it followed by two more. heading down you will see a 4th hog stop at your location "get in." as the passenger seat is highlighted.

from here the player is driven to the cliffside pod location. by the abandoned one, as a full out war goes on in the air above, krestles being seen fighting banshees pelicans taking off from other points.

once you get to the cliff side, a pelican can be seen crash landing into the mountain above. two shade turrets opening fire on anything that gets close. your orders shifting to taking out that AA and finding the survivors. The AA is easy to take out though you have to get out of the hog to do so. down bellow you find the marines wounded getting up while the others move to follow you. foe hammers comes in to pick them up like normal. a marine is seen manning one of the shade turrets and shooting down some banshees as this happens.

You are instructed to get on unlike normal at which point you get a birds eye view as you are carried to the cliff face where you are told to jump out just above the ground the marines holding the line with snipers and long sight lines, the objective being to protect them until another pelican can return.

For this you get a sniper rifle like normal. but also one of the marines has a rocket launcher and there are some supply pods (if someone can model h2 supply pods for CE) nearby with MA5 and pistol ammo.

This defense is a bit harder then normal hostile wise, an example is one of the groups dropped off is some sword elites dropped right on your head from a spirit. while another group has a shade turret dropped off and starts pounding the cliff face. thankfully snipers are good at range.

taking out the covenant an armed pelican will come back shooting down another banshee as is enters the valley. you are informed there is one last group at a rock slide. they are dug in but need spartan support.

This is where the first major story change happens. as you approach instead of just UNSC soldiers you see orion soldiers armed with the standard MA5. these soldiers will give you some heavy fire support and are even shielded (these are introduced so in later levels you have an ally who can withstand the flood)

the final section also has two wraiths dropped in to pound the rock slide one up top just outside the map one inside where you can take it down. the one outside is taken down by a long sword shortly after it is dropped off, so is the one inside if you don't destroy it fast enough.

The mission ends with foe hammer picking you up, and you moving to the rescue mission.


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The truth and reconciliation
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This mission starts like normal with you and a squad of marines landing just bellow the ship, though unlike normal some key changes are made the marines are ODSTS (sorry all mods must put ODSTS here.) and a few Orion troopers. all the ODST troops are armed with shotguns, the orions armed with snipers.

As you clear the first cliff point another lance of marines will be dropped in behind you. they will secure the landing zone. pushing up through the first half is just like normal. until the final zone before the landing pad.

here you will see several the shade turrets shooting into the air as a pelican comes in acting as air support taking them down, with its chin gun as it lands more ODST troops for the final push. The covenant knows we are here and there is heavy AA in the final clearing take it out.

AS you move into the next area with the grav well you will see not only is there a lot of shades but an active phantom and 4 hunters. though before you can react a low flying long sword will swoop between the ship and the valley and blow up a good chunk of the defending troops leaving you only having to fight the shade turrets like normal. once the landing zone is cleared two pelicans will fly in to drop off troops. one is instantly engaged by banshees forcing it to retreat while covenent troops start coming down the grav lift.

fighting the troops you will eventaully clear the landing zone as two marines get in shades shooting down the banshees and allowing the rest of the marines to approach.

upon going up the lift only one Orion trooper follows, none of the ODSTs do as they secure the lift its self instead you have standard marines. on entering the main chamber marines move to secure the doors shotguns aimed at them. sure enough the moment that first sword elite enters it eats buck shot and the chaos starts. forcing the marines into the larger door where they state the obvious. as you turn around to return you will hear a sound of the grav lift the large door opening to show more marines entering the place. a few moving with the rest while the others start securing the entry zone.

As you push through the ship more and more areas are secured. example when you clear the lower level of the hanger. upon returning on the second level you will see a pelican dropping more troops on the first. as you get to the third level a marine is manning a shade turret on the second.

once you get the control room. A major story shift happens, A few marines stay behind like normal but this time a few more come in to follow you. the first brig also has crew men and soldiers in it though no weapons. upon opening it they will follow one of your marines back to the bridge or cortana will tell them to head to the bridge.

once you clear out the room for keys and free him the mission continues like "normal" until you get back to the bridge where you see a marine with a shotgun kill a golden elite most the marines in the room dead or wounded. but the bridge is secured.

instead of being cut off foe hammer will state she is in the bay and waiting. allowing you to move through the last part with ease." while on the way there you hear some marines say things like "so we calling this beta base then?" "you sure the covenant won't try to take this back?" "Hey its our ship now. if we can fix it we can get out of here."


note: with this missions changes the level "keys" will be swapped to the same ship as this level.with it heavily under marine control but the spec ops teams having been sent in to retake it at the same time the flood started to overwelm it.