The Master Chief did as she said. A technician sprayed a topical anesthetic on his neck. The skin tingled, then went cold and numb. The Master Chief felt layers of skin incised, and then a series of distinct clicking sounds that echoed through his skull. There was a brief laser pulse and another spray. He saw sparks, felt the room spin, then a sense of vertigo. His vision blurred; he blinked rapidly and it quickly returned to normal.

“Good... the procedure is complete,” Dr. Halsey said. “Please follow me.”

The Captain handed the Master Chief a paper gown. He slipped it on and followed the doctor outside.

A field command dome had been assembled on the range. Its white fabric walls rippled in the breeze.

Ten MPs stood around the structure, assault rifles in hand. The Master Chief noted these weren’t regular Marines. They wore the gold comet insignia of Special Forces Orbital Drop Shock Troopers—“Helljumpers.” Tough and iron-disciplined. A flash of memory: the blood of troops—just like these—soaking into the mat of a boxing ring.

John felt his adrenaline spike as soon as he saw the soldiers.

Dr. Halsey approached the MP at the entrance and presented her credentials. They accepted them and scanned her retina and voiceprint, then did the same to the Master Chief.

Once they confirmed his identify, they immediately saluted—which was technically unnecessary, as the Master Chief was out of uniform.

He did them the courtesy of returning their salute.

The soldiers kept looking around, scanning the field, as if they were expecting something to happen. John’s discomfort grew—not much spooked an Orbital Drop Shock Trooper.

Dr. Halsey led the Master Chief inside. In the center of the dome stood an empty suit of MJOLNIR armor, suspended between two pillars on a raised platform. The Master Chief knew it was not his suit. His, after years of use, had dents and scratches in the alloy plates and the once iridescent green finish had dulled to a worn olive brown.

This suit was spotless and its surface possessed a subtle metallic sheen. He noted the armor plates were slightly thicker, and the black underlayers had a more convoluted weave of components. The fusion pack was half again as large, and tiny luminous slits glowed near the articulation points.

“This is the real MJOLNIR,” Dr. Halsey whispered to him. “What you have been using was only a fraction of what the armor should be. This—” She turned to the Master Chief. “—is everything I had always dreamed it could be. Please put the suit on.”

The Master Chief stripped the paper gown off and—with the help of a pair of technicians—donned the armor components.

Dr. Halsey averted her eyes.

Although the armor’s components were bulkier and heavier than his old suit, once assembled and activated, they felt light as air. The armor was a perfect fit. The biolayer warmed and adhered to his skin, then cooled as the temperature difference between the suit and his skin equalized.

“We’ve made hundreds of minor technical improvements,” she said. “I’ll have the specifications sent to you later. Two of those changes, however, are rather serious modifications to the system. It may take... some getting used to.”

Dr. Halsey’s brow furrowed. John had never seen her worried before.

“First,” she told him, “we have replicated, and I might add, improved upon the energy shield the Covenant Jackals have been using against us to great effect.”

This armor had shields? The Master Chief had known that ONI research had been working on adapting Covenant technology; Spartans had standing orders to capture Covenant machines wherever they could. The researchers and engineers had announced some breakthroughs in artificial gravity—some UNSC ships were already undergoing trials with the grav systems.

The fact that the MJOLNIR armor possessed shields was a stunning breakthrough. For years, there had been no luck back-engineering Covenant shield tech. Most in the scientific community had given up hope of ever cracking it. Maybe that’s why Dr. Halsey was worried. Maybe they hadn’t worked out all the bugs.

Dr. Halsey nodded to the technicians. “Let’s begin.”

The techs turned to a series of instrument panels. One, a slightly younger man, donned a COM headset.

“Okay, Master Chief.” The tech’s voice crackled through John’s helmet speakers. “There’s an activation icon in your heads-up display. There is also a manual control switch located at position twelve in your helmet.”

He chinned the control. Nothing happened.

“Wait a moment, please, sir. We have to give the suit an activation charge. After that, it can accept regenerative power from the fusion pack. Stand on the platform and be absolutely still.”

He stepped onto the platform that had held the MJOLNIR armor. The pillars flickered on and glowed a brilliant yellow. The pillars started to spin slowly around the base of the platform.

The Master Chief felt a static charge tingling in his extremities. The glow intensified and his helmet’s blast shield automatically dimmed. The charge in the air intensified; his skin crawled with ionization. He smelled ozone.

Then the spinning slowed and the light dimmed.

“Reset the activation button now, Master Chief.”

The air around the Master Chief popped—as if it jumped away from the MJOLNIR armor. There was none of the shimmer that normal Covenant shields had. Was it working?

He ran his hand over his arm and encountered resistance a centimeter from the surface of the armor. It was working.

How many times had he and his teammates had to find ways to slip past a Jackal’s shield? He’d have to rethink his tactics. Rethink everything.

“It provides full coverage—” Dr. Halsey’s voice piped through the speakers. “—and dissipates energy far more efficiently than the Covenant shields the Spartans have recovered, though the shield is concentrated on your arms, head, legs, chest, and back. The energy field tapers down to a hair under a millimeter so you don’t lose the ability to hold or manipulate items with your hands.”

The lead technician activated another control, and new data scrawled across John’s display. “There’s a segmented bar in the upper corner of your HUD,” the technician said, “right next to your biomonitor and ammunition indicators. It indicates the charge level of your shield. Don’t let it completely dissipate; when it’s gone, the armor starts taking the hits.”

The Master Chief slipped off the platform. He skidded—then came to a halt. His movements felt oiled. His contact with the floor felt tentative.

“You can adjust the bottom of your boot emitters as well as the emitters inside your gloves to increase traction. In normal use, you will want to set these to the minimal level—just be aware your defenses will be diminished in those locations.”

“Understood.” He adjusted the field strengths. “In zero-gee environment I should increase those sections to full strength, correct?”

“That is correct,” Dr. Halsey said.

“How much damage can they take before the system is breached?”

“That is what you will learn here today, Master Chief. I think you’ll find that we have several challenges in store for you to see how much punishment the suit can take.”

He nodded. He was ready for the challenge. After weeks spent traveling in Slipspace, he was long overdue for a workout.

John slid back his helmet visor and turned to face Dr. Halsey. “You said there were two major system improvements, Doctor?”

She nodded and smiled. “Yes, of course. ” She reached into her lab coat and withdrew a clear cube. “I doubt you’ve ever seen one of these before. It is the memory-processor core of an AI.”

“Like Déjà?”

“Yes, like your former teacher. But this AI is slightly different. I’d like to introduce you to Cortana.”

The Master Chief looked around the tent. He saw no computer interface or holographic projectors. He cocked an eyebrow at Dr. Halsey.