0002 hours, September 7,2552 (Military Calendar) ONI underground facility, planetReach.

Fred followed the trail of odd symbols along the left-hand stone wall until they twistedinto a spiral mosaic and vanished into ever-smaller curls. The symbols were part of therock, com.posed of glittering mica inclusions in  the granite matrix. There were a series ofsquares, triangles, bars, and dots, similar to Covenant calligraphy he had seen—but at thesame time it was simpler, cleaner, and when Fred focused on them, the characters  seemed to blur around their edges and fade from his stare.

He blinked, and the symbols were there again.

Following these symbols like a trail of bread crumbs had been his primary mission for thelast five days. Dr. Halsey and the Spartans had explored the extensive caverns, hoping tofind two things: a way out, and what Dr.  Halsey called "the most impor.tant discovery ofthe millennium." She had, however, refused to speculate on what exactly this discovery would be. "I'm a scien.tist," she'd told them, "not a soothsayer."Fred would have settled for finding an airhole to the surface— but he recognized that thesymbols were important, too. They were important because the Covenant thought they were impor.tant. And that made  whatever Dr. Halsey was searching for worth finding, ifonly to keep the enemy from getting it.

The Covenant hadn't stopped digging overhead, although the pace and methods they usedhad changed. There had been no further explosions. There was only the constant andgentle scraping sound of equipment as they slowly but steadily re.moved the mountain.Every hour the sound intensified as they140HALO: FIRST STRIKEdrew closer. Fred had set his audio filters to screen out the noise so he could concentrate.

Five days. It hadn't seemed that long. They worked, they rested, they slept, and theywaited. Dr. Halsey had taught them word games like twenty questions and simple cipher,at which they all became extremely  proficient—so much so that she quickly stoppedplaying. Dr. Halsey was not a graceful loser.

The time had melted away. Maybe it was the darkness, the lack of any temporal referencelike the sun, moon, and stars, but the hours had lost their meaning.

He paused to stretch his Achilles tendon, recently stitched and fused by Dr. Halsey. Asidefrom some stiffness, it was almost back to normal. He had almost torn the tendon off,running on the injury.

Dr. Halsey had patched them all up; she had even flash cloned Kelly a new partial lung,which she successfully grafted. In her tiny field medical kit, the doctor had a handheldMRI, a sterile field generator, even a shoe-box- sized clone tank for organ duplication.

She had also installed the new MJOLNIR parts in their exist.ing armor. These upgradeswere in field-testing and not certified, she had ex lained, but she gauged their needsufficient to justify the risk of using the new equipppment.

Kelly received an improvement to her neural induction cir.cuits, giving her twitchresponse time a speed boost. Vinh had a new linear accelerator added to her shieldsystem, effectively doubling its strength. Isaac had a  new image-enhancing com.puterinstalled. Will received a better tracking system on his heads-up display, which improvedhis accuracy at distances up to a thousand meters.

Fred flexed his bare right hand. Dr. Halsey was installing his upgrade now—new sensorsthat would boost the sensitivity of his motion tracker. Without the single gauntlet, Fredfelt vul.nerable. The Master Chief would have  told him not to rely on his armor orweapons—rely instead on his head. It would protect him better.

He wondered how Blue Team—John, Linda, and James—had fared. And what of the restof his own team? Had anyone at the generator complex survived?

ERIC NYLUND141He didn't want to think about them—but he couldn't help it. Maybe it was the darknessand the constant weight of the earth around him.

What if they died here? Not died fighting, but just died here. In a way, that wouldn't be sobad. Fred had faced death a dozen times, brushed so close to it he had stared it in the faceuntil it blinked and turned away.

This was different, though. He didn't want to die, not without knowing if the otherSpartans were still out there fighting. Not if they still needed him.

He sighed and absentmindedly brushed his fingertips across the odd symbols. They wereas smooth as glass, and their edges were sharp. These crystals could be a naturalphenomenon. He had seen similar inclusions in  the museum on—Fred felt a hot pain in the tip of his finger. He drew his bare hand away and a tiny track ofblood smeared the rock.

The glittering symbols on the wall took on a greasy cast, and the reflection from hishelmet lights thickened and almost seemed to be absorbed by the minerals.

He flicked off his helmet lights. The symbols in the rock emit.ted a faint illumination oftheir own: a soft reddish glow like heated metal. The light intensified and spread acrossthe spiral on the wall, starting from where his  blood had fallen; those sym.bols warmedto a pleasant orange, then yellow-gold.

A new symbol in the center of the spiral appeared that hadn't been there a second ago ...or perhaps it had been, but had lain just beneath the surface. It heated and becameincreasingly visi.ble, a single triangle that  glowed white.

Fred was inexorably drawn to this central figure. He reached for it; there was no heat. Heslowly stretched and touched the symbol with his exposed fingertip.

Warm white light raced along the spiral of symbols, then traced a path down the hallwayand into the distance. The entire cavern seemed sudden alive with radiance and shadow.Even with the step-down luminosity filters  in his helmet, Fred had to blink and squint.

The wall before him rumbled and seams a peared at the cen.tral figure, dozen of linesthat curved in a radial pattern—and then pppulled away to reveal a corridor behind.

142HALO: FIRST STRIKEFred realized that he was holding his breath. He exhaled.

This new corridor was twenty meters high—large enou h for a titan to stride down itslength. It vanished into the distance, a straight line that gggently sloped deeper into theearth. The floor was paved with asymmetric blue tiles patterned to look like waveslapping upon a shore. Four-meter-tall symbols of gold were centered and inlaid into themirror-smooth walls.  These gi.ant triangles, squares, bars, and circles began to emit thesame soft light... and Fred felt his foot shuffle forward.

He stopped, shook his head, and looked away. He checked his radiation counter; it pulsed,and then fell back to a normal back.ground count.

He keyed the COM. "Doctor Halsey, I think I've found what you've been looking for.Sending video feed now. Copy?"There was a long pause. The COM was open, but Dr. Halsey wasn't responding.

"Doctor Halsey, copy?""Yes," she finally said over the COM. "Don't move, Fred. And don't touch anything.Excellent work. Kelly, Isaac, Vinh, Will— meet me at Fred's location."Fred wanted to stare at the gold symbols and the light they cast, but something warnedhim that this would be dangerous. He had long ago learned to listen to that inner voicewhen on pa.trol or in the heat of battle. It  had saved him from dozens of am.bushes. Hekept his eyes on the dirt floor of the tunnel. There was something too fascinating andnearly familiar about those sym.bols. They reminded him of the Greek mythology  thatDeja, the Spartans' first teacher, had taught—legends of hauntingly beau.tiful creatureswho lured the unwary to certain death. Sirens.

He checked his rifle. The ammo counter read full, but he hit the magazine release andvisually confirmed it. He slapped the clip back into the receiver. This simple operationcleared his head.

He detected four blips on his motion tracker—they glowed green, indicating fhendlies.

Kelly, Vinh, Isaac, and Will jogged up next to him, weapons ready.

"What is this?" Will whispered. The golden glow reflected in his helmet's faceplate.

ERIC NYLUND 143"Careful," Fred warned them. "Filter the light. Go to black-and-white imageenhancement."He got four blue acknowledgment signals, and then Fred switched to BWIM display.Funny that he hadn't thought of that for himself. Only when the safety of his team was atstake did he think clearly.

Dr. Halsey ran along the tunnel and halted, panting, next to the Spartans. "Yes," she said,wheezing. "Yes, this must be it—what Ackerson was searching for. And most likely"—sheglanced at the roof—"what they are  looking for, too, I imagine."Dr. Halsey ignored the curious symbols and the light, and strode into the new corridor."Hurry," she told them. "I fear we've set something in motion, and our visitors upstairsmight know it, too."Fred assembled his team to form up around Dr. Halsey. Kelly took point, and the rest ofthem created a loose box around her.

Dr. Halsey handed Fred his missing gauntlet. He took it and wriggled his fingers into thearmor, pulled it snug, and sealed the locking collar around his wrist. Diagnostics ran andconfirmed that his armor was whole again. His  motion tracker pulsed on his heads-updisplay.

The hallway changed as they continued down its length. The golden light faded along theceiling, and inky black covered its expanse; tiny stars winked on and twinkled. Fredadded color to his display; he wanted to see  this. Moons wheeled overhead; silver-grayorbs, pockmarked with meteorite impacts, spun in wide orbits. Along the walls, tall greenbamboo-like grass sprouted and grew up the curved surfaces.

Dr. Halsey brushed her fingertips along the wall, and the grasses wavered at her touch."Semisolid holo raphy," she said without halting. "No visible emitters. Interesting. Weshould in.vestigggate this later," she said and increased the pace of her stride. "If there'stime."The holographic environment cycled to an arid moonscape: deep craters and sterile light;it became a volcanic world with lava flowing alongside them. The air wavered with heat.In each transformation the golden symbols  remained on the walls, lead.ing them throughthe illusions.

144HALO: FIRST STRIKEThe corridor emptied onto a landing ............