1. RECURRENCE

one

RECURRENCE

H igh in the mountains, surrounded by the radiant wilderness of a vast pine forest, the entrance to the Tesera Mine lay just below the snow line. Its passageways ran deep into the earth, the hard stone laboriously carved into by Miners of the Mystics for over half a century.

Once occupied by hundreds, now dwindled to a fraction. Trickling water and winds did little to ease the haunting stillness that had claimed it. Oliver never got on well with those they lost to the Wandering Horrors, but not even he could ignore the strangeness of it. From inside Maji's hovel, he heard nothing. Not a whisper, not a shout.

"I can't believe someone tried to steal something, as if Sigma wouldn't notice."

Fortunately, he had Maji to fill the silence while she clipped dead leaves.

Oliver stood by the raised hearth, holding an odd plant with bird-like blossoms over the magical, smokeless fire provided to them by another Sentinel, Theta. According to Maji, this plant was dangerous and anything dead needed to be burned immediately. The Touch-Me-Not, she called it. Oliver didn't pretend to understand why she kept such a plant, neither did he have the head to listen to her explain it. He was content to just hold it, hands gloved to protect his skin from its poisonous pecks.

"Nobody ever tried to pull that with Tau," Maji continued.

He watched a shrivelled leaf flutter in a downward spiral. The flames leapt up to engulf it, momentarily turning a bright purple and hissing. He kind of liked that.

Maji chuckled lightly. "He would have tossed them out on their backsides so quickly."

Oliver couldn't muster a smile or a response. Losing Tau hurt the same as when it happened. Every night he slept, if he slept, terror haunted his dreams. Every day he went to work and saw Sentinel Sigma, he was reminded of his failures, of why Tau wasn't there instead.

"Anything new from the vein at all?"

He cast Maji a baleful look. She was only asking to make conversation, not always keen to let silences be. Ordinarily, he didn't mind, but this wasn't a conversation he wanted to have again.

All the same, he muttered, "Nothing at all."

She knew this. It was only two weeks ago he had uncovered a thin blue vein within the stone of their working drift. Until now, discoveries of anything blue led to one disaster after the next. None of which he or any of his friends asked for.

"The one time I find something and it leads to exactly nothing." That same, tired fury rekindled, setting ablaze his insides. His grip on the pot tightened.

Maji pulled it out of his grasp before it broke. Oliver dodged her pitying look, and stepped over yet more plants to her bed. He dropped into it and rolled over to watch while Maji busied herself stroking the bird-flowers with a gloved finger. They didn't seem to like that very much, flapping their pale yellow wings to get away. Too bad for them, trapped by their own stems as they were.

Maji was short and plump, with golden skin and thick, glossy black hair often kept in a plait. Oliver liked it that way, and he wasn't the only one appreciative of her appearance.

"Where's Luce?" he asked.

"Mining."

Daft question.

Naturally, Lucetta was mining. She was particular about how she spent her free time, which was never reserved for anything other than more work.

"I guess I'll go down too," he said, sitting up.

That earned him a reprimanding look. "You should sleep. I know you haven't for the past three days."

At least. Oliver made a face, then waved her over. "Come here, then."

Pointedly, Maji set the plant down by the hearth. Discarding her gloves to the floor and hopping past the abundance of plants, she threw herself onto the bed beside him. Its damp-damaged wood creaked in complaint as Oliver rolled onto his back so she could nestle against his side and wrap an arm around his stomach.

He held her close, taking comfort in the warmth of her body, stroking the side of her face and brushing away stray hair. This was something he'd always wanted to do, forever denied by his curse until his friends let him keep the fur mantle, imbued with Sentinel magic. He rarely went without it now.

"Do you remember when we first met?" asked Maji.

Oliver pursed his lips. He'd come fresh out of passing his test to become a miner and the first thing he'd done was fall down a winze, breaking his leg. Maji had tried to help before Tau found him and mended his bones.

"Yeah. Fine moment. Why?"

Maji snickered. "Sometimes, I wonder if you would've seen it if I hadn't shouted to warn you."

"You forget how much of a meathead I am."

She leaned up on an elbow to peer down at him, deep brown eyes glimmering with sincerity. "You're not as stupid as you keep saying."

All he could do was strain a smile. If he hadn't been so stupid, so useless, then Tau would be here with them. Not that Oliver would say this out loud, knowing Maji would try to refute it. When she settled back down, he rolled to hover over her and dropped a firm kiss to her forehead. Owlishly, she blinked up at him.

"I'm not in the mood to sleep," he said. "I'm going down. Wanna come?"

"No, thanks."

Oliver took a moment to squeeze Maji's stomach rolls. He snorted at her indignant, "Hey!" and swung off the bed to wander out of the hovel. Unlike him and Lucetta, Maji had her many, many plants to occupy her. Lately, they needed an extra helping hand since Sigma's light wasn't as powerful as Tau's.

Tau had lit the mine with beautiful enchanted spheres resembling the sun during the day, and moon at night. Now, in their stead, clusters of twinkling stars adorned the rugged ceilings. Tau's magic was pure light, whereas Sigma's was more in the realms of a night sky. It was nice, plumes of mist mantled the stone above in varying shades of purple and blue, but it wasn't Tau.

Oliver walked past the myriad of homes, burrowed into the hard rock of the mountain, with arched doors and circular windows. Although they were slowly regaining their numbers, most hovels were still empty. The ghostly feel of the passageways was unlikely to disappear any time soon.

Down in one of several cage lifts, Oliver leaned against the metal bars, rattling his frustrated sigh. He ran his fingers through his hair. The sides were getting too long again.

He wished he hadn't sold off all his sewing material to save for a trip to the Library of Portals. A trip that now felt more like a pipe dream.

He wished he had something to do besides think about Tau.

Past various drift openings, Oliver strode to his station further back. Most of the working drifts too were inactive. Since the Wandering Horror attack, they were down to barely a room full, more than half of whom were new and all foolhardy enough to brave a mine now considered cursed.

Mister Pavlov, the mine owner, did what he could to raise their image with flyers and parties to garner interest. Sure, they lost two Sentinels, something both devastating and nearly unheard of, but that was only due to the vast amount of magical activity within the mountain. Ergo, there were many riches waiting to be gained. That was how Pavlov liked to spin it, and although Oliver didn't know what an ‘ergo' was, the arsehole's methods were working.

"You should be sleeping," said Lucetta the second Oliver entered their working drift, her black curls ashen from dust, and grime coating umber skin.

"Had a nap." The lie slipped from his tongue with practised ease.

His friends cared about him, but their insistence he should sleep had become frustrating after the first few times. Nightmares of ghastly human-plant hybrids clawing his skin, of insects crawling around his insides had tried, and broken, Oliver's endurance when they first began two months ago. He knew his inability—and sometimes outright refusal—to sleep was taking its toll, but he was tired of lying about why he couldn't stand the thought of closing his eyes when regret and sorrow dogged him so relentlessly.

Securing his hard-boiled hat, he grabbed a scaling bar and pickaxe from the hutch near the entrance and approached the same area he'd been working around for the past two weeks. He eyed the blue vein spanning across a formation now resembling a fat stalactite. The last time they found such a vein, blue double doors appeared shortly after. Hoping it would summon another set, Oliver didn't dare dig into it.

"Good morning, Oliver."

He started, only now spotting Helen crouched near Lucetta, her sleek red hair tied at the nape. Oliver should have known she'd be here. These days, Helen always worked as Lucetta's partner whenever her fiance, Anna, wasn't up for it.

"Shit, sorry Hels. Hullo." Oliver shimmied into a crevice and set to work. He wasn't feeling up to idle chatter, which Helen loved.

Once in a while, he resurfaced from relentlessly breaking down stone, coughing to clear his airways of dust. He ran gloved fingers along the blue vein, old leather snagging on its rough texture as he sipped water from his canteen. The vein was as long as his forearm, thin like a blood vessel, and bright as the summer sky.

Every time he touched it, the vein lit up, as if alive.

Hurt chipped away at his heart. He missed his boyfriend so damn much. Oliver didn't know if Tau was even alive. All his magic had disappeared with him. He'd seen Tau on the brink of death before, but his magic had stayed.

Oliver tried not to think about what that could mean, on the verge of crumbling as it was.

If nothing else, he longed for closure. If he could at least know for sure Tau was dead, then maybe he could work toward moving on. There remained that persistent hope though, a festering wound at this point, that convinced him his Sentinel was still alive, somewhere . Maybe still caught in Ondine's clutches.

Ondine.

The name burned like an infernal curse.

Oliver clenched his hand into a fist, his anger singed like hot iron. He dragged his knuckles across the blue vein. It gleamed, tempting him to break it.

Maji and Lucetta had fought hard to stop Tau from being dragged away by black tendrils, but it was him with the inhuman strength. It should have been him to act. Instead, Oliver had only watched as the love of his life was taken from him. Doing nothing, saying nothing.

A burring noise, harsh in its echoes, pulled him from his defeated recounts. He squinted at the bright, sizable globe floating midair into the drift, its aura dark blue. Its vividness waned, transforming.

Benighted armour scintillating like stars adorned Sentinel Sigma's tall body, gloomy clouds with silver linings forming the cape. The jut of two long and straight horns occupied the helmet's temple, the light emanating from behind the visor a deep, dark blue.

Sigma's arrival suggested they were nearing a discovery. It also meant that whatever they were about to uncover would be risky at best, deadly at worst. Or…

Oliver's heart stuttered with hope. He threw himself back into his corner and swung the scaling bar with renewed vitality. Who would make the discovery was usually the fun part. Now, it displaced frayed nerves alongside his fervent desire to find Tau himself.

Behind him, Helen made a sound of delighted surprise.

He took it as his cue to stop and darted to join Lucetta in peering over Helen's shoulder. Inside the schist, she uncovered a tiny dome dusted in pale green—a handbell.

Oliver bit the inside of his cheek to stop the quiver in his chin.

"Whatever you do, don't ring it," said Lucetta.

"I know, I know."

Oliver braced himself, hand gliding to the hatchet tucked away at his belt. Lucetta reached to hold the clapper between pointer finger and thumb, while Helen carried on chiselling the surrounding stone until they released the bell from its rocky prison.

It was of tarnished bronze, the delicate flower embellishments faded, like its leather strap. Helen pushed up from her knees and carefully handed the bell to Sigma. The Sentinel vanished from sight with a faint snap , as though someone had clicked their fingers together.

Ordinarily, it took a while for a Sentinel to return from wherever they went to deal with Dire artefacts and entities—to avoid human casualties. Some kind of dark dimension, based on what Oliver saw once. This time, another snap announced Sigma's near immediate return.

Helen, Lucetta, and Oliver stood from where they had taken a seat among rubble. Sigma's enormous black claw held out the bell, ringing merrily.

"Not dangerous, then?" Lucetta hesitantly took it. It rang again, resonating through the drift.

An angry sigh hissed past Oliver's lips. He threw his scaling bar to the ground with such force, it speared the stone and rattled where it stood upright.

Every time they found something, which wasn't even often, he hoped it would lead him to Tau. Of course it hadn't again. His frustration distorted into a raging fury. All the simmering anger and guilt now at boiling point.

Oliver cried out, slamming his fist into nearby schist. Bones audibly cracked. The stone crumbled under the impact, pieces dropping away, splitting the blue vein. Hand pulsating in agony, he stared.

There was nothing behind the schist. Nothing inside it. What was left of the vein dulled until it faded to grey.

There was nothing .

A pathetic whimper shuddered free. Were it not for Lucetta's arms circling his midriff, he would have buckled to the ground. Oliver cradled his broken hand against his chest as full lips pressed to the back of his head.

"We'll find him," Lucetta murmured into his hair. "It's just taking longer than expected."

"But what if we don't?"

What if he was left wondering what had happened to Tau for the rest of his life?

Oliver stumbled over rubble as Lucetta coaxed him to approach Sigma, who held out Their gigantic claw toward him. He hissed, easing the glove off. A faint and deep blue light enveloped his outstretched hand. The crunch of bones before they clicked back into place was nauseating, but eased the pain and swelling of skin. Embarrassed, Oliver nibbled his lower lip, glancing up at Sigma with appreciation.

An abrupt force against his upper back launched him forward, out of the drift to collide head on into a wall.

He dropped to the ground, dazed. Ignoring the searing pain in his face, he looked over his shoulder and saw Sigma struggling against a tall being, darker even than the shadows. No more than a silhouette, flickering like the lick of a flame. It shoved Sigma with brute force, pinched pointed claws together, and rammed its fist directly through Sigma's chest. Metal rived, its shriek echoing.

Sigma stilled. Black armour turned grey—to stone. Crumbling to gather in a pile of porous aggregates, rolling to a standstill at Oliver's feet.

He froze at the sight as the tall shadow moved away, down the main passageway. Pointed hood unmoving, extravagant robes soundlessly aflutter, a faint, singular glimmer vanishing.

All at once, it occurred to Oliver that Tau had just manifested. That he'd murdered Sigma. That he was leaving, flickering in and out of sight.

Helen came scrambling out of the drift along with Lucetta, who punched Oliver in the shoulder, unrooting him from where his feet had burrowed into stone. Oliver dashed after Tau, jumping over Sigma's rocky remains on his way down the main passageway.

"Tau, come back!"

Darkness abruptly swallowed them.

All of Sigma's twinkling stars had vanished from the mine. Oliver skirted to a halt with a startled gasp. Two bodies collided into the back of him, sending him sprawling to the ground with a grunt. He heard Lucetta cry out. The sound of someone tripping, followed by swearing, echoed through the passage.

"You okay?" Oliver asked the dark.

"No, my knees. Always my damned knees!"

"You guys, what just happened?" Helen's voice quivered. "Was that Sentinel Tau, did They kill Sigma?"

"Ollie, the blue doors showed up," said Lucetta.

"What?" Oliver's shout bounced around the abyss.

He pushed up and groped his way back, reaching for Lucetta, only for his knuckles to rap harshly against something hard. Oliver sucked in a breath at the pain. Bringing his hand up to his lips, a faint orange light poured through the passageway to his right. A group of miners shortly followed, a man at the forefront holding a torch. Oliver glanced around. He wasn't even anywhere near Lucetta, only by a mining hutch.

"You lot are such idiots," sneered the man with the torch—Lauper. Ugh.

Grimacing, Oliver eyed the make-shift light, of old timber burning with Theta's fire. Smokeless and a deep orange, hints of purple at the lip of the flames.

"You're not allowed to do that," Oliver said. Then immediately regretted it.

"That's rich coming from you, considering you set the entire place on fire with this."

Yep, that was it.

Oliver scowled but could say nothing.

"Unlike you," Lauper continued, haughtily, "I've learned from the last time we were left without light—hey!"

Oliver had stopped listening. He grabbed Lucetta and Helen by the arms and ran to the cage lift while they had enough light. He slammed the gate shut and brought his hand down on the button before spotting the state of Lucetta's knees. The denim was ripped and skin glistened with blood. The orange glow slipped away as the cage rattled and shook on its way up, their surroundings abyssal once more.

"I should've taken that torch off him," Oliver grumbled. "You okay?"

"I'll live. Ollie, if that's Tau…"

"That–That isn't him." Oliver really wasn't so sure.

"But if it is," Lucetta hissed underbreath, "and he's after Sentinel magic…"

The realisation hit him like a hatchet to the gut. Oliver swore.

Tau had done something like it before with Sentinel Nu. Sigma's magic must have been what the glimmer was.

Oliver kicked out a leg, hands shaking with the need to act. When the cage finally jerked to a stop, he fumbled around for the latch and shoved the gate open. His gaze fell to a trail of shimmers on the ground. Not unlike streaks of water sparkling in sunlight, casting a faint glow and leading through the passageway toward the next cage.

He knelt by the fluid, carefully prodding it. Both warm and cold.

It sent a chill through his very soul.

Tau.

Oliver bolted into the next cage with Lucetta and Helen in tow, following the trail all the way directly to Maji's hovel. Empty, with pools of the shimmering fluid smearing the rugs.

"Hang on," said Lucetta before Oliver darted back out. She grabbed a burning log with Theta's fire latched on its end. Its deep orange glow swung forward into the passageway, casting a long flickering shadow in front of Oliver's feet as he ran.

Reaching another level, several panicked miners and guards yanked open the gate and packed inside, flattening Oliver against Lucetta.

"Watch it!" he snarled, squirming out of the crowd, shoving to make way for Lucetta and Helen to get out. The gate slammed shut behind him and the cage rattled away.

Headed down the passageway, Oliver caught flashes of emerald and immediately understood what the others were trying to escape.

The shadowed imposter hung within the tunnel ahead, held up by thick roots protruding from the ground, trapping his arms, his legs. He struggled against the restraints, wood shredding under sharp claws. Oliver dashed past the dangling, struggling shadow to Maji's nursery. A thick wall of branches and foliage blocked its jagged entryway. He turned back to face the struggling being still held up. Oliver clenched his fists, torn between helping and fighting him off, unsure if the being was Tau, ignoring the twist in his heart that said he already knew.

"Maji! Are you alright?" Lucetta came to stand beside him.

"Yep!" Maji called through. The barricade retreated into the crevices of stone, and she cautiously emerged. "That's not Tau, is it?"

"Not a chance," said Oliver with far more confidence than he felt. "He killed Sigma and took Their heart. We're guessing he's after Nu's."

Roots shredded like paper. The shadow lunged for Maji. Oliver moved to shield her, quick to grip both of the imposter's armoured forearms. He brought his knee up. It connected with the lower stomach. Oliver grunted at the pain bolting through his leg, the muscles like iron, but he'd sent him scrambling backward, at least.

Refusing to think about it, Oliver pulled his fist back. His knuckles slammed into the masked face. The force of it sent the imposter into the adjacent wall. He slumped down to the ground and Oliver hissed at the throb now in his hand, shaking it to get the ache out.

Both Lucetta and Helen had the sense to stay near Maji while Oliver approached the being. He appeared to be unconscious, head hanging low.

Oliver startled, heart clobbering his insides, as wreaths of sunflowers formed midair nearby, bringing a sunny yellow light. He knew they were Maji's.

Sigma's heart was nowhere in sight. All Oliver saw was more of the shimmering fluid pooling from underneath the figure's mask, down the broad chest. His jaw locked with regret and fear. Cautiously, he toed the shadow's knee with a boot-clad foot. Not for a second did Oliver think he'd killed him. His hand wasn't even broken this time.

Neither did he think a metal claw would snatch him up by the throat. Dangling off the ground, he stared into bright flashes of green. So much like Tau's and yet, nothing like him.

Oliver kicked at anything he could reach, but his strength, even if inhuman, was no match. The claw around his throat clenched more tightly. Stars popped along his vision, he rasped against the cinching pressure on his windpipe.

Feebly, Oliver kicked again. Weakly, he smacked at the vambrace.

Roots sprang up to entwine the shadow again. This time, the dark Sentinel didn't move, only squeezed harder.

Knowing what awaited, Oliver gasped, "I love you."