Four: Prologue to World Conquest

The Mantle's Approach and its escort of Liches dropped back out of Slipspace in an asteroid belt above a broken world in the Khaprae System. Spartan and AI had been silent the whole short ride there, but when the Lich's shields stopped shimmering, John called Cortana's name softly.

"Still here," she sighed, sounding more tired than he had ever heard her.

But with confirmation that she was still alive, he had to keep moving forward and hope that she could hold it together long enough for them to stop the Didact. He stood up and looked out. "This must be Zero-Three," he said, looking up at the almost glowing arc of the ring, "Why are we bypassing it?"

"Because the Composer's not on the ring anymore."

The Lich and its fellows were aiming for the UNSC base, built into one of the largest asteroids.

"What are you waiting for? That station's not going to save itself."

John obeyed the implicit order and climbed down to the Lich's airlock, covered by an energy field. It was only active enough to keep the atmosphere in; none of the aliens had expected him - or anyone, really. They died quickly as a result, and he stepped up to the control panel. "Cortana, you got this?"

"I… I think so." She sounded hesitant, so unlike her usual self-assurance. He remembered that she'd sounded like that coming out of High Charity, too.

"I'm right here, okay?"

She made a noise of assent, and he pulled her out and slotted her in. The AI took control of the Lich and opened up a COM channel with the station.

"This is UNSC Master Chief to base. Do you read?"

"Yes, I hear you!" Female. Older, panicked. A scientist, probably; even though there was a UNSC presence, the station wasn't really a military outpost. "This is Sandra Tilson of Ivanoff Station! We're under attack!"

"They're after a Forerunner artifact that you took from Installation Zero-Three."

"How do you know about that?!"

"Doctor," the Spartan said firmly, "We need you to protect the artifact until we arrive. Send whatever-"

His anticipation whispered, chills rising along his spine. He went to one knee next to the console and curled an arm around Cortana's avatar. She turned at once to clutch at him with ghostly hands, her form rippling and distorting with the effort of holding back her outburst. "Send whatever troops you have to defend it. When we dock with the station, we can take command from there."

"Okay," Tillson replied, sounding at least a little relieved now that she had an objective and someone who could handle everything once they arrived, "okay, I'll do it."

The COM channel closed, and Cortana finally released a nearly incoherent scream of rage, electrical discharge racing through the Lich. John couldn't make out everything the personality spikes said, but he bore the abuse calmly, without so much as a word of protest no matter how harsh hers became. At last, the episode ended, and she collapsed to the control panel and wept. "I'm sorry! I just… can't stop them!" she sobbed, reaching for him, even as the Lich came in for a shaky docking with the station, "It's like a thousand of me arguing all at once!"

"I know, mell. I know."

She shivered faintly at the endearment - still calling her beloved in the Common Tongue, as if they were still in the early phases of their relationship - and sorted herself back into her chip. She felt even hotter when he returned her to his armor; she was still absorbing data at a dangerous rate, but he couldn't ask her to stop doing that any more than she could ask him to stop breathing. What they were doing was essential to both of their beings.

John stepped off the Lich and killed the Covenant who tried to stop him from entering the station, reopening the COM channel to the resident scientist. "Doctor Tillson, are you there?"

"Yes, I'm still here! The soldiers are on their way!"

"Good. You need to issue the order for all civilians to evacuate the station." He sprinted across the landing bay, doors grinding open as he approached. Just beyond, a security guard went down under a hail of pink quills from a Needler, but he squeezed the trigger on his sticky detonator again and took the aliens with him.

"We've been trying!" the scientist told him, "The Covenant - they've already taken over the landing bays!"

"Send us your coordinates," the Chief ordered, "We'll see what we can do about clearing an evac route on our way to you."

The hall let out into one of the hangars. There was a Jackal in the air, and he fired automatically, killing it and saving the guard it had been leaping for. The Marine stayed back to protect a few scientists while the Spartan moved forward.

Every alien that crossed his path went down. "What can we do to keep the Covenant out?" he asked, even as more Phantoms swooped in to drop off still more troops. The Marines were fighting hard, but there were only so many of them, unlike the Covenant who seemed to be as numerous as the Flood.

"The Harbormaster controls can erect a barricade over the bay," Cortana answered, "but we'll have to locate them."

The area around him momentarily clear, John swept the area and spotted a likely looking console on the other side of the bay, beyond a line of more than a dozen Grunts and Jackals. He palmed a grenade, then launched it in a perfect arc into their midst. It took out a third of their number and sent the rest stumbling. Rather than waste time killing them - time another Phantom could use to drop off more troops - he raced past them and found the Harbormaster console. Cortana quickly walked him through the process, and the barrier shimmered into place, letting the Spartan turn back to fire on the Covenant.

With bullets coming from two directions at once, he and the Marines made short work of the remaining Covenant, even the ones that came in from a side chamber towards the tail end of the fight.

The Marines seemed to be both surprised and awed that he'd returned from the dead - and just in time, too. They took orders without protest and started rounding up the civilians for evacuation, while John continued on through the station.

A group of security personnel were under fire from a plasma turret; John leveled his DMR and put a bullet between the Grunt's eyes, then moved his fire to the Sangheili who took over at the gun's controls. The alien went down before it had even fired a shot.

There was another Sangheili, but it went the way of the first, and its cadre of Unggoy and Kig Yar followed not far behind. Then the Spartan led the way through the machinery to a wide stairwell, the security team close behind, weapons up and ready.

There were more Marines at the bottom of the stair, trying to stop the Covenant from pushing down from above. Their lieutenant spotted him first and gave way without hesitation, letting John hurl a plasma grenade up. It caught an Elite full in the chest, and the alien only had just enough time to roar in futile fury before it detonated, killing it and a few of its underlings. That turned the tide and let the Spartan lead the charge up the stairs.

But as they ran, an orange scan wave passed through the station, sparking at the equipment. "Didact doesn't know where the Composer is!" Cortana managed, her voice more shaky than he had ever heard it, "Just that it's on the station."

There was another flight of stairs beyond, with still more Covenant. There were still a few security personnel holding out against a Field Marshal and his cadre. While the Sangheili was still unaware of his presence, John finally pulled out the sticky detonator he'd taken from the very first Marine and tracked with his anticipation, then pulled the trigger, waiting only long enough for the charge to adhere to the Elite's armor before pulling it again. He dropped the detonator to his thigh plate, bringing his DMR around a second later, and got the alien between the eyes.

That sent the Grunts into fits of terror, no matter how high-ranked they were, and the security teams rallied together at his back, gunning for them. When the aliens were dead, John gave them the same orders he'd given the teams below - collect the civilians for evac - and kept moving.

Just as he was finally getting close to the scientist's coordinates, he stumbled across a group of her panicked coworkers hiding in a side chamber behind a blast door. "Help us!" one of them begged, "A pair of Hunters forced their way in! Take this - it's calibrated for heavy armor."

It was a thruster pack, not quite as omnidirectional as a jetpack but better suited to the low ceilings of the base. Good for dodging the Hunters' fire.

The Spartan entered the lab, already lifting his sticky detonator and following the phantom projections of the anticipation. The Hunters were running rampant, destroying the equipment and chasing the scientists. He waited until one turned its back on him, then fired and detonated two charges, one right after the other.

The alien collapsed before it could crush the scientist it had been trying to kill. The other roared and turned to the Spartan, close enough that it tried to charge.

John was already out of the way, dropping the now-useless detonator - he'd used up the last of his ammo for it - and pulled out a pair of plasmas he'd taken from the Field Marshal. Just like he had so many years ago, he got in behind the Hunter, climbed it, plunged the grenades into the bare worms of its back, and then leaped away.

The Hunter spun to follow him - and then blew apart, spraying orange gore all over the lab. But most of the scientists were still alive, so he called it a win. He took a brief moment to breathe, then said, "Cortana, Tillson?"

His HUD flickered, her response incomprehensible, but then it cleared. She said, "Tillson's behind the door over there."

He followed her nav point to the door controls. The scientist was waiting just inside and greeted him nervously. "I desperately hope you know why all this is happening," she said, leading him further into the chamber overlooking the Composer, "because to be honest, my objectivity isn't doing me a whole lot of good right now. Hold on, I'll start us down."

John waited until they were moving, then said, "The device you recovered is a Forerunner weapon. The commander of that ship wants it back."

The scientist stopped, then turned back to look at him. "'Wants it back'?" she repeated, "You don't think you can remo- it can't leave the station, you know that, right?"

"We don't have any choice, Doctor."

Tillson shook her head. "It's not a matter of choice," she insisted, "It took three months, and the biggest starship the UNSC could throw at it just to relocate it here." She gestured to the machine as they descended enough for it to come into view. "Unless you're a lot stronger than you look, it's not going anywhere."

She was right, but with no word from the Fleet, they couldn't just leave it where it was. The Didact could not be allowed to reclaim the Composer, which left only one option. "Can you give Cortana access to the station's supply manifest?"

"What for?" Even as she questioned, she pressed a few keys on the console, adding the AI to the list of personnel with authorized access to the station.

"The Didact's ship is a hundred miles long, and has more advanced technology in a hundred feet than the UNSC has in the entire fleet. If he gets the Composer, he will use it against us, and we don't have anything that can stop him," said the Spartan, "If we can't move it, we have to make sure he can't either."

Tillson caught on fast. "We have years of research invested here," she protested, but he could see in her eyes that she understood. Denial was just the first stage of grief.

"Inventory lists seven excavation-grade HAVOK mines," Cortana said, pulling up the list on one side of his HUD, "Just one of those would turn this base into a piñata."

The scientist's face fell.

"I'm sorry, Doctor," the Spartan said, as gently as he could, "With the kind of damage the Composer can do, we can't afford to let it fall into enemy hands, the same way the UNSC couldn't let the Covenant discover the location of Earth during the war.

"Keep routing your people to the evac centers. Once we take care of the Composer, you won't have much time."

She let out a heavy breath, and he saw her eyes go glassy with tears. "I'll… make sure the nukes are primed so you can… detonate them remotely."

He nodded in thanks and turned to go.

"Maybe next time you rescue us…"

He turned back to look at her.

"...you can give us more time to pack?"

"Next time," he said with a nod, and left the research lift. The hatch to his left was broken, sparking with electrical discharge, so he went right instead and entered the main chamber, where the Composer was kept. "Cortana."

"Yes?"

"Just in case… How do some of your more bloodthirsty personality spikes feel about playing Trojan horse?"

There was an immediate response - a hiss of delight and a number of battle cries. John approached the Composer and laid a hand on its side, and he felt some of the spikes leave his neural lace and jump into the machine, the AI's presence cooling slightly in his mind. The Composer's glow flickered just for a moment, so fast he would have thought he imagined it otherwise.

"They'll slow him down for a while," said Cortana - right before an explosion rocked the station.

"Doctor, what was that?!"

"The Covenant…" the scientist managed, sounding utterly stunned, "The Covenant just shot down the first evac shuttle."

"The station should be equipped with outer turrets," Cortana piped up, "If we can reactivate them, I can program the station's defenses to provide cover for the evacuation."

"Okay - okay, I'll send you the coordinates."

Once she had them, the AI put up a nav point to direct him. Beyond the hatch, a security guard was taking a breather from the fighting, but he pushed himself to his feet when he saw the Spartan. He approached the control panel for the doors ahead and unlocked and opened it.

"Officer, seal the door behind me."

"Yes, sir."

John headed through the hatch and up a short catwalk to the hallway above. As he did so, another scan wave passed through the station.

The Forerunner's mind pressed in once more. 'You impress me, human. Your singular valor will be preserved and studied, once your composition is complete.'

The station shook again, power flickering. Something must have overloaded somewhere, because the hall went dark around him, the hatch ahead slamming shut. There were two Covenant still on this side, however: a Grunt and a Jackal who never saw him coming. There was a service tunnel nearby, and he used it to bypass the lockdown.

The hall eventually opened up into an airlock loading zone filled with Covenant. He stuck the Sangheili with a plasma grenade before it noticed him, then turned his guns on the rest of the aliens. They were just Grunts and Jackals, no challenge - until more started trying to come in through the airlocks. His anticipation warned him in advance, with enough time for him to get to each airlock and hit the button to vent them back into space.

When all of them were gone and the airlocks were secure, he kept moving through another hatch, down another catwalk, and into another hallway. There he found a group of scientists pinned down by more Covenant. He darted in and climbed the Sangheili directing the attack, plunging his knife into the alien's neck. It was dead before it hit the ground, but he had already moved on, yanking one of the Kig Yar around and driving the knife down through its skull. A few bullets put the Unggoy out of their miserable terror, letting the Spartan see to the scientists.

"They ran!" one scientist cried, terrified tears streaming down her face, a Magnum clutched tight in her shaking hands, "The security team assigned to us, the second the Covenant showed up! How could they do that?!"

One of the other scientists opened the hatch to a side chamber, presenting the Spartan with an autosentry. He accepted it with a nod of thanks and said, "Find Doctor Tillson. She'll direct you to the evacuation area."

The sole remaining guard herded his charges back the way the Spartan had come. John continued on, following the main hall to another catwalk, and another airlock loading dock beyond that. Like the one before, there were aliens everywhere, and he gunned them down as fast as he could, venting the airlocks again. Once they were dead, the lockdown was lifted, but he claimed the Jackals' carbines before moving on.

Another scan wave rushed through the station. "Maybe the Great and Powerful Didact shouldn't misplace his things!" the AI – or one of her personality spikes – hissed with great venom.

They entered the defense control room. Despite their active camouflage, the Spartan's anticipation still showed him the SpecOps Sangheili at the controls. That explained why Cortana couldn't activate the defenses remotely; they were being manually overridden.

He fired on the alien at the console first, careful not to damage the equipment. The Sangheili whipped around to return fire - just in time to catch a plasma grenade with its face.

The Spartan had already turned to attack the second Sangheili, who charged him, plasma sword in hand. He ducked the first swing, punched the alien in the face, hard enough that it brought its shields down by more than half. Then he caught the alien's wrist and damned near crushed it, keeping the blindingly hot sword away while he unloaded an entire clip from his Magnum into its chest.

When it fell, he went for the console. As he did, Cortana's personality spikes slipped through. "My intervention is the prerequisite for success!" one cried, before another snarled right after, "Why should we save them?"

John slotted her in anyway, calling for Tillson over the COM. "I'm here," the scientist answered, "Any luck?"

"Cortana's bringing the defense grid back online now."

"I hear it," she said as the guns perked up and began firing on the Covenant ships swarming the base, "We'll broadcast the final evac orders."

"The nuke?"

"We're rigging it now. Meet us back on the upper platform, and we'll help you get it to the artifact."

He closed the COM channel and pulled Cortana from the system. As she returned to his armor, she whispered, "Chief? If we - pull this off, and actually get back to Halsey? Don't tell her how bad I got. Please?"

She specifically mentioned Halsey, because they both knew keeping secrets in the Fleet took so much effort as to be pointless. They might not know what was being hidden, but they would know he was hiding something - which might unravel the harmony they had worked so hard to build. "I won't say anything," he promised, and headed out.

As usual, there were Covenant in his way. He fought through them to an observation deck overlooking the Composer.

There were no living humans left. Instead multiple Phantoms swooped overhead, while the aliens under them cheered and worshipped the machine. "Keep them away from it!" Cortana cried, "Stop them, Chief! You ca-an't let them tell him i-it's here!"

The Spartan broke through into the main chamber and sprinted for the nearest Mantis. "Doctor Tillson, the Composer's location's compromised," he said over the COM, climbing the back of the machine to the cockpit, "You've got to get that nuke down here!"

"I-It's not ready yet!"

"Ready or not, we need it now." He felt a brief pang of guilt for snapping at her, but if he wanted to save the lives of everyone on the station, he didn't have time to be gentle. He narrowed his focus and let the anticipation guide his hands on the Mantis's triggers.

Wave after wave of Covenant rolled into the room, slamming against him and trying to overwhelm his defenses with infantry and cavalry alike. Grunts with fuel rod guns, Jackals with carbines, Elites with Ghosts, Wraiths, Banshees, and Phantoms all bore down on him. But despite all of that, none of them had any more success than the thousands of their fellows who had come before.

"Doctor Tillson!" John called, unloading a full chamber of rockets into a fleeing Phantom, "Where's the warhead? Doctor Tillson!"

"Head back to the elevator platform. I'll keep trying to raise her." Cortana sounded anxious, with a bare edge of hysteria.

He steered the Mantis over to the platform and jumped out, racing for the hatch. When he entered the lift, the AI said, "The HAVOK mines'll be in one of the cargo bays. Start us up."

Despite how it appeared, the console was fairly intuitive. He tapped a few keys, and the elevator groaned and started to rise. As the Composer came into view, his anticipation alerted him - not with a whisper, but with a scream. He threw himself backward, even as Cortana cried, "Chief! Immense Casimir wave building outside the atrium!"

The Mantle's Approach ripped the roof off the base with the wailing, screaming grind of rending metal. One of the many cranes was torn free of its mount and smashed into the elevator platform, throwing them to the floor. The Spartan automatically curled up to protect himself, hands covering Cortana's chip. The crane fell away with another sharp jolt, and John pushed them up to see what was happening.

A vibrant, violent orange tractor beam ripped open what was left of the base. The Composer was pulled free of its moorings and rose out of sight, and the Mantle's Approach moved away with it.

"Cortana, see if you can raise Tillson." The Spartan got back to his feet and went to the console - what was left of it - to start pulling information about the rest of the station. When Tillson had given Cortana clearance for the station, the AI had in turn extended it to him, and he took full advantage of that now.

"Tillson, Sandra K. Female, fifty-one years of age," Cortana said dreamily, before her voice slowly turned strained, "Doctor of Archaeology, Pegasi Institute - got her! Bio-signature stable on 350-level, B-deck."

"Thank you, Cortana." He wanted more than anything to call her by another endearment; enedhen - my heart - had never failed to bring a smile to her face, but he didn't dare. Too many cameras, and there would be a review, an investigation - assuming they all survived.

The elevator resumed moving, then stopped. John hit the manual release for the doors, then ran through the halls until he spotted Tillson in the panicked milieu. "The Didact's taken the Composer," he told the scientist, stepping up to a console nearby and slotting Cortana in, "Get these people to the evac centers!" To the AI, he said, "Tap the flight deck; find us something that can carry a payload. But defense systems first - get ready…"

His anticipation saw it before it happened. The Mantle's Approach was drawing near again, the Composer charging at its heart -

Without warning, the ship shut down, the Composer going dark. Over the COMs, Cortana's personality spikes let out screams of triumph.

"Cortana, defense systems! Target the Composer!"

"That, I can do!"

She brought all the guns around and had them empty everything they could into the heart of the Forerunner ship. It wasn't completely accurate, but it did enough damage that when the Didact overrode the spikes' control, he immediately closed up the ship and started moving away.

'I will give you this one small victory, human. Savor it while it lasts, for I will win this war, too.'

The scientists and security teams around them cheered as the Approach turned to go. "Let's go," said Cortana, "There's a Broadsword waiting for us in Hangar C-11; if we hurry, we can catch him."

On the way down, John helped the security teams mop up what was left of the Covenant, but more often he came across tired guards and scientists carrying injured or dead friends on makeshift stretchers. A sense of reality was returning to the base, and with it an overpowering grief.

"These people are gone," Cortana whispered. They both wanted to stop and help more, but they both knew they couldn't afford to.

"And more will follow if the Didact reaches Earth," John said, giving voice to the thought.

After a moment, Cortana whispered, "They'll pair you with another AI. Maybe even another 'Cortana' model if Halsey lets them."

"That's not going to happen." His voice was just as quiet, but resolute. If they tried to give him another Cortana, he would refuse without hesitation.

"It won't be me," she nearly whimpered, "You know that, right?"

He paused in an empty hall. "Cortana." When she appeared on his HUD, he said, "It's not over. Not yet."

"Not yet," she repeated.