Duobus

During the next three days, Optimus and Megatron drilled several hundred feet into the unforgiving wall. The metallic rocks became so hard the two mining mechs started blasting just to make progress. Utterly exhausting work, and all the laser energy being expelled quickly heated the surrounding area. Hot panels against exposed wiring was not a very pleasant sensation, but nowhere near as annoying as dust clogging intake valves. Optimus coughed more than he worked. He hated this place!

"Just like the good old days!" Megatron shouted over another explosion. He aimed low and fired his cannon once more, tearing another crater into cave wall.

Optimus squinted through the clearing smoke. More rock. Did it ever end?

"Are we making progress?" he asked.

"I'd say a good ten feet."

"Only ten?" Optimus walked over and stood right next to Megatron in disbelief. All that work for ten feet?

"I've run into slabs that required ten days just to clear a passage the length of my arm. Stop complaining!"

"I just--" Optimus froze, he swore he just felt the ground shake under his feet. "Wait...did you feel that?"

Another tremor. Dust and rocks pattered across their armor.

"The ground unstable. We have to--"

But there no longer was a ground to stand on. Optimus' fall jolted to a halt and he realized Megatron had him by the hand. Rocks pelted his face when he looked up--he didn't dare glance down.

"Swing up!" Megatron snarled. "Hurry!"

Optimus kicked his legs forward for momentum. He swung himself high enough to grab Megatron's other hand. Just as Megatron started pulling him up, he heard a loud CRACK--and reality became a dizzying spin between screaming, darkness and cold wind ending in a clang that sent dull pain though his back. Megatron's full weight pressed down upon his chest, adding to his discomfort.

"Ugh," Optimus groaned. "Are you all right?"

"I'm...functional," Megatron's deep, growling voice was right in his audio, and Optimus became uncomfortably conscious of the other's cycled air puffing hotly against his intact ear finial. He tried to shut it out. His rival wasn't supposed to make him feel this way!

"So, what now? Is there any way back up?"

Megatron sighed and Optimus wished he would move, or at least stop breathing on his audio, but he didn't. "The grappling hooks are still up there." Finally, he sat up and aimed his lights at the silver walls. There were no handholds.

Optimus grew slowly aware that the floor underneath and the surrounding walls were smooth paneling rather than rock. Most were rusty, but a few places still glistened eerily in the harsh lightning. The air around them hung in a stillness so absolute it was as if time forgot to exist.

"Megatron, wait! Go back to the left!"

"What?"

"Just do it!"

The light beams jogged left and glistened across images engraved upon the metallic wall. Huge images twice Megatron's height. One was planet Cybertron surrounded by purple fog and flanked by Autobot and Decepticon sigils. The symbols didn't surprise Optimus...the figures on whose chests they were placed nearly stopped his fuel pump.

"That's...us!" Megatron squinted. "But how?"

"I don't know." Optimus stared, confused and even afraid. Who carved this? Why? When? He looked closer and spotted a seam running down the center of Cybertron's image.

"This doesn't make sense!" Megatron said, joining Optimus by the wall.

The second he was beside Optimus, the ground shook so hard they stumbled to stay standing. Grinding sounds punctuated the wall before them sliding apart. It left a space just large enough to slip through.

Megatron walked right on inside.

"Megatron!"

"Oh, come on! Where's your sense of adventure?"

"Grrr..." Optimus pushed between the doors, startling when they slammed together behind him. He was glad Megatron had the rations lashed to his cannon...the doors would've crushed them had Optimus been wearing the pack.

The first thing he noticed was the glowing white coolant river running from a waterfall spanning the entire wall on their left. This tunnel looked relatively tall and narrow, offering enough room to walk side by side. The walls here were clean and shiny, making Optimus and Megatron's dirty forms appear drab by comparison, and the coolant river provided enough light that Megatron shut off his shoulder lamps.

Optimus knelt to dip his hands in the coolant. This was it--he had to remove his mask or he couldn't drink. How strange...this moment didn't make him nervous at all. There were no disfiguring scars or blemishes to hide. In fact, people said he had a very beautiful face with delicate cheeks and a small, heart shaped mouth.

He retracted his mask and drank his fill. Exposing his visage offered a strange relief, as if his armor no longer felt too tight for his framework. He could feel Megatron's gaze roaming over his naked features.

"So..." Megatron drank as well, though not as much. He was too busy staring at Optimus and, oddly, smiling. "...this is the face of Orion Pax."

"Your point?" Optimus sneered, closing the mask again.

"You look so young." Megatron shook his head in obvious disbelief. "And here, I thought you were covering an unsightly scar like this," he pointed to his own face.

"Oh? Sorry to disappoint you."

"I never said I was disappointed." Megatron grinned once more and started blithely down the narrow corridor, leaving Optimus more confused than ever. When did that fanged smile stop intimidating him? When did he start anticipating its appearance?

"Though..." Megatron went on once Optimus caught up, "I wonder why you still bother wearing it now that I've seen your f--"

"It's part of who I am now," Optimus cut him off.

"Reeeeally?" Megatron drew the word out as if Optimus lacked the intelligence to understand standard speech. "I wonder, what are you hiding from?"

Again, Optimus' temper turned over like a tempestuous ocean. "You say that when your mouth has been running ever since I reconnected your vocal processor. Is it to annoy me...or does being quiet mean you have to think?"

"Don't change the subject."

"I didn't change the subject."

"This isn't about me!" Megatron snapped.

"No, this is about us."

"And you're still hiding behind that battle mask."

The swirls inside Optimus boiled over in flaming tsunamis. Before he knew it he'd slammed Megatron against the wall and thrust his face inches from the Decepticon leader's.

"I'll take my mask off if you take your mask off, you son of a glitch!" he growled, pulling Megatron forward and smacking him into the wall again for good measure. To make his point, he retracted the plates covering his nose and mouth. "I can tell you're in pain from this. We both are. You parade around, claiming you haven't lost a thing, but we both know you lost just as much as I did!"

"What use is there in crying over a situation I can't change?" Megatron replied with equal venom. He didn't want to face the subject, but Optimus wouldn't let him dodge it this time.

"Last time I checked," Optimus spoke through clenched teeth, "pain is the same whether you're an Autobot or a Decepticon."

Their eyes remained locked, a battle of wills in which Optimus saw himself and everything he said reflected in Megatron's tight-lipped stare.

Reality spun a circle and Optimus was suddenly pinned against the wall with Megatron's voice snarling in his audio, "Pain consumes you alive if you let it. It opens an abyss in your Spark and swallows you like a black hole. The strong are the ones who can fight the abyss."

The hole inside Optimus, a collection of faces long gone, dragged the churning ocean of self control towards his eyes where it erupted in a single, golden mech fluid tear.

"The strong may fight their inner black hole, but the brave aren't afraid to show they have one."

Megatron's jaw clenched. His lips pulled back until the entire length of his fangs gleamed in the eerie lighting. Whatever self control he had wavered like a scale thrown off-balance. He narrowed his eyes, reached up and wiped at his cheek. Mech fluid clung onto the dirt coating his purple fingers. He brought his fingertips to his lips and tasted them.

"Hm."

Then he roughly passed his thumb across Optimus' cheek, smearing dirt on the flawless metal, before lifting it towards his mouth and ingesting the liquid residue.

"Isn't it ironic that our bitterest pain is made of the sweetest fluid produced by our bodies?" Megatron said in a tone so nonchalant it was as if the previous events never happened. He shoved Optimus carelessly aside and resumed walking down the narrow corridor. At the end, where the path curved sharply to the right, he paused and spoke softly, "I see the men I lost every time I offline my optics. I see the look on Starscream's face when his body started to explode. The difference between us is I don't dwell. I don't sit and wonder if I could've saved him because I already know the answer is no."

Megatron turned the corner, effectively cutting off their conversation. Optimus stood there without so much as a sharp retort to throw at Megatron's retreating back.

.o

The next meal Optimus and Megatron ate together would be more awkward than the time Optimus learned what the human saying "pop your cherry" really meant.

He spent the entire time avoiding Megatron's gaze, which remained fixed on his exposed face. It slid over and around his mouth each time he bit into an energon cube.

"Would you stop staring?" They were the first words Optimus said since their quarrel near the mysterious doors.

Megatron's smile flitted across his face. It made his eyes squint into crimson slivers. "Uncomfortable?"

"Tch."

"I suppose it's curiosity. How many people have you kissed with that mouth?" His grin became mischievous. "I suspect you're a virgin."

"My sex life is none of your business," Optimus said curtly, turning away.

"You mean your lack of one," Megatron laughed.

"I'm sure you're just as deprived. Big war, annoying enemy, doesn't leave much time to share Sparks with anyone, does it?" Optimus palmed his last energon cube and smirked at how fast he cut Megatron's laughter off. His gaze went to Megatron's mouth, taking in the full, round lips that, even while relaxed, seemed to curve downwards in a natural frown. He wondered what it would feel like to have that dangerous thing glide over his throat and--

Where in the world did THAT thought come from? Optimus tore his gaze off his rival's face, ignoring the derisive laugh stirred by his uncomfortable shifting.

Sighing, Optimus pushed his tired, dirty body upright and glanced over at Megatron, who reclined while propped up on one elbow like a misplaced sculpture on the clean, silver ground. He'd gained a lot more respect for his greatest rival. There were some moments were he found himself enjoying his company--even when they argued, because having someone to argue with was far better than wasting away alone--and he couldn't help but wonder if things between them would've been different had they gone through all this and met again with the knowledge they possessed now. Would they still go to war? Would they still be rivals on opposing sides?

"Would you have a bond right now if we hadn't gone to war?" Optimus asked, more to fill the silence than for the sake of actual conversation.

"I don't know." Megatron answered coolly. "I've felt attraction before. I know what lust feels like. But love..." Then he clicked his tongue and stood up, shaking his head as if his thoughts tasted sour. He met Optimus' gaze and a strange sadness glimmered in his eyes. "People like us don't have time for love. And even if I did have the time, I doubt the relationship would've worked."

"Who was--"

"Nevermind!" Megatron groused. The word stretched the space between them into a canyon. Optimus sympathized all too well with Megatron's sentiment on love. Mechs like them were programmed to be fighters, not lovers.

They said nothing more. Megatron picked up the backpack and they resumed their course down the narrow corridor. The roar of the coolant waterfall was a constant companion on their left. Optimus noticed the coolant river beside them becoming more agitated and wild. Their path tilted into a shallow incline. Wherever it led, it carried them even deeper into the planet.

Megatron rounded another corner and thrust his arm out sideways, blocking the way. "Wait."

Optimus was jolted from his thoughts. "What?"

"The terrain is too steep to walk on. I think I can traverse it in tank mode, but I'm not so sure about your tires."

"I don't see anything I'd crash into."

"This is unknown territory--I don't recommend just rolling down."

"I think you're overly paranoid." Optimus smiled sadly. He found it strangely liberating to make choices without worrying about the well being of his army. The same thought carried guilt on its heels...how could he think such a selfish thought?

Megatron rolled his optics. "So says the same mech who didn't want me to walk through the first door."

Optimus shook himself back into the present.

"People change."

"What do--"

Optimus transformed and gunned it over the side.

"You IDIOT!" yelled Megatron.

Optimus ignored him and enjoyed the almost weightless feeling of acceleration. He saw the corridor floor flatten out again. His mind reeled as he imagined himself smashing flat against the wall like a human soda can. He pumped his brakes, expecting his momentum to slow, but the deafening shriek of his tires brought a whole new reality into being. In a last, desperate attempt to stop before he contacted the large, glistening panels at the corridor's end, Optimus turned sideways. His vehicular form jack knifed and rolled violently for a nauseating eternity. He'd never remember the impact--one minute he was rolling and the next he heard Megatron shouting his name.

"Uhhhh..." Optimus forced himself upright and transformed, "stop yelling!"

"You moronic Autobot!"

The floor proved too smooth even for Megatron's treads. Optimus heard his surprised grunt as he came barreling down the metallic slope. Megatron's treads ran in reverse to no avail. He finally transformed, tumbling head over heels until he crashed into Optimus. The impact rang like an explosion that reverberated around the enclosed space as they toppled in an ungraceful heap of moving, tangled limbs.

"Oof!"

Optimus gazed up at his rival's sneering visage and tilted his head. Megatron stared back, his expression unreadable. Their faces were literally inches apart--so close Optimus felt Megatron's cycled breath waft against his lips.

"Well..." Optimus said. He found himself floundering in the red optics he didn't want to look into, but there was no other direction he could turn without making the situation even more awkward, "I guess treads aren't everything."

"I suppose not," Megatron replied curtly. He pushed off Optimus' chest and stood up, directing his gaze at the paneling before them.

Optimus regained a vertical base and followed his companion's steady gaze. The engraving he saw on the first door also existed on this panel, save for one small difference: their likenesses were looking at each other instead of facing forward.

"What do you suppose this means?" Megatron held his chin between thumb and forefinger.

"I'm not sure, though..." Optimus frowned, "The last door didn't open until we stood next to each other like the image."

"So?"

Optimus turned his head. There was no denying a connection between their actions and the doors opening.

"Megatron, look me in the eyes."

Snorting, obviously not believing, Megatron fixed his eyes on Optimus'. Nothing happened. He looked away, uncomfortably shifting his weight. "This is foolish!"

"Give it time. Come on, let's try it again."

Megatron's discomfort made itself obvious in the way he shuffled his feet. Optimus found himself once more in the line of those bottomless red eyes that made him feel emotions he wasn't supposed to think about right now. The danger in Megatron's gaze was almost tangible, and Optimus silently wondered what it tasted like.

He saw Megatron relax, a flicker of hardness leaving his optics just long enough to glimpse the haunting images he saw above ground. A vulnerability so fleeting and dim it never quite reached the surface. Anger, fear, passion and grief surrounded Megatron like a scarlet fog so thick one had to wonder how he saw where he was going in life.

Everything around them shook as the panels split and slid apart. Whining noises indicated ancient joints that hadn't moved in eons were grinding to life.

Optimus didn't notice the passageway was open until Megatron cleared his vocal apparatus. It broke the spell cast over the moment, waking time from its sleep and returning his mind to the task at hand. They squeezed through the doors only to have them snap shut once they passed.

No going back. No direction to go but forward.

This corridor looked even weirder than the one before. For one, it smelled awful, like sulfur. Optimus' gaze traversed the vaulted, dome shape of the room. The walls were faceted mirrors glistening like polished gems. When Optimus peered over the side, he discovered the source of the smell was a lake of sulfuric acid.

"Whoever falls is dead," he said.

"Then I have a suggestion," Megatron made a face. "Don't fall."

The only way across was a menacingly narrow walkway. Optimus squinted at it...the block had a peak running down its center. Not even his Metallikato training, which included balance and agility, would get him to the other side safely.

"This is perfect! How in the Pit do we cross that?" Megatron growled.

Optimus measured the twin inclines with his gaze. He nodded to himself.

"We go at the same time."

"What?"

"If we hang onto each others' hand, we can balance each other."

"You're insane!"

Optimus' temper stirred again. "Look around you, Megatron! The only way across is over that pathway." He jabbed a finger at the block, "Something is guiding us. Maybe it's Primus himself. All I know is we'll never find out unless we work together. So come on, aren't you the least bit curious about where we're heading?"

Megatron twisted his mouth to the left and shifted around on his feet. He glanced from the block to Optimus and back. His face pulled. Finally, he tugged their ration pack off his cannon barrel and shoved it against Optimus' chest.

"Carry this, it'll even out our weight."

He was shaking.

"Megatron..." Optimus softened his tone. "What is it?"

"Noth--"

"Tell me."

The Decepticon leader stopped and licked his lips. His gaze flickered between the block, the acid and the ground at their feet. The usual, feral gleam in his eyes had been replaced with something cooler, lonelier.

"Millennia ago, shortly after my creation date, I saw someone fall into an acid lake much like that one. He slipped...he clung to the edge for ages before he fell. It's...probably the most painful way to die. He was right in front of me, begging, and I didn't help him. I could have stretched out my arm and saved him, but I did nothing. I watched him dangle and I did nothing."

"Are you serious? Why?"

Megatron's icy glare died before it could freeze the air around him. He turned to look out over the motionless, glistening lake far below and said, "I was afraid."

The revelation struck Optimus somewhere near his Spark. He never imagined Megatron afraid of anything. Hearing such an admission reminded him that his rival was, underneath it all, just another Cybertronian like himself. And while he sympathized, Optimus also knew he needed Megatron focused on getting across the narrow pathway.

He didn't realize he'd reached out until he felt his hand rest on Megatron's large, purple shoulder. "I won't let you fall. You'll be fine."

"You're so predictable." Megatron's eyes narrowed. He glowered at the offered hand. "Let's get this over with."

They joined hands and approached the block. Light glanced dangerously off its sharp edges, mocking them with its smoothness. Optimus could feel Megatron tensing like a locking mechanism and gave his hand a reassuring squeeze.

Their feet took the first step in unison. Optimus kept his balance easily while Megatron scrambled for purchase on his equilibrium.

"Don't look down," Optimus said. "Step with me."

And they moved together, two unwitting circus tightrope walkers toeing the razor's edge between life and death.

"You're doing just fine."

"Stop--coddling me." Megatron growled. His voice lacked its usual confidence and his grip was iron. Then his foot slipped and he barely...barely...suppressed the yelp Optimus knew hung like a fog around his vocal processing unit. The servos in his hand clamped down until every joint nearly crumbled from the pressure.

Beneath their feet, the narrow walkway jiggled. Optimus noticed the opposite side looked a little higher than he remembered. The block jolted a second time, wrenching them another foot lower.

Optimus realized this was A Very Bad Thing.

"Uh...Megatron? Can we..." He chose his words carefully, afraid that alarming Megatron would place them in worse danger, "...can we hurry up a little?"

Another jolt rocked the entire path.

Megatron lost his footing.

Optimus collapsed sideways, the sharp peak of the walkway digging painfully into his side as he bore Megatron's full weight on his right arm. Megatron never screamed, but the look on his face was sheer, slack-jawed terror.

Don't let me fall, those eyes said. Please, whatever you do, don't let me fall!

"Brace your feet on the side!" Optimus yelled. The hydraulics in his arm were reaching critical pressure. If they ruptured...he didn't want to think about it. "When I tell you to, start walking. I'll pull you up!"

Megatron's fingers shook so hard it was a wonder he kept his grip. Optimus' own Spark throbbed uncomfortably within its chamber. He couldn't lose Megatron like this!

"Megatron!"

"I--I'll fall if I move..."

"You'll fall if you don't move! Help me help you!"

Optimus saw Megatron's legs kick out and rest against the wall. He grabbed his forearm, willing whatever strength still left in his system to hold out a little longer. Progress was slow and slippery. Optimus almost tumbled backwards once he got Megatron back on his feet. The walkway crumbled around them--and if they didn't get across soon, they'd never reach the ledge on the other side.

"We're sinking!" Megatron gasped, shivering. "You idiot! We're sinking! You should have dropped me! Your foolish compassion is going to kill us both!"

"Stop it!" Optimus kicked himself the second he shouted. Telling Megatron not to panic while panicking himself wouldn't help matters! His growing terror bled right through their joined hands. He felt Megatron rush forward and followed before his own balance wavered. The metal beneath his feet seemed more slippery than a greased axel. He lived in constant terror that they'd both topple.

And then, suddenly, they were at the other side. The walkway juddered downwards another six feet.

Optimus shoved Megatron against the flat ledge. "I'll give you a boost."

"You'll fall!"

"I can stand on this, I just can't walk on it. Let me help you up. Then you can pull me up."

Another inch lower...Optimus gritted his teeth.

"Fine..." Megatron growled. "But you're a fool to place so much trust in me."

"Not a good time to argue."

"Touché."

Optimus angled his feet so they pointed out to either side and slowly, delicately, squatted with his fingers interlocked like a platform. Megatron stepped backwards onto it. Optimus strained the servos in his legs and shoulders as he shoved the heavier mech up towards the platform. Megatron hauled himself over the edge. Optimus lunged and caught the ledge a millisecond before the entire walkway crumbled. He felt the chain holding the backpack on his shoulder break, but couldn't do a thing to stop it. The energon they so carefully mined plunged into the sickening muck below, and a faint purple glow filled the chamber as the energon cubes melted away. Hissing punctuated those future meals reacting with the acid. Six months of fuel cut down to six weeks for two bots--and that was if they rationed their intake to a cube a day.

Pieces of the ledge broke away. All Optimus could hear was the sizzle of metal much like his armor melting into slag.

And now, the only thing between him and the same demise was the three feet of ledge under his fingertips. He gazed up into the unreadable visage of his rival. Megatron hadn't moved since the walkway fell. His crimson optics were more frigid than the coldest planets in the universe. He knelt, like he probably had so long ago in the mines, and peered down at Optimus. Shadows of the past flickered across his dirty face.

Optimus looked up. "Megatron..."

No response beyond a frozen stare. Fear or anger, Optimus couldn't tell.

"Ever since I heard your name, I've longed to see you in this position, Optimus." Megatron began, his voice a monotone. "My next action will determine whether you live or die. I have your life in my grasp. I have control of your fate."

Optimus' fingers began to slip. "M-Megatron..." He hated himself for begging the moment the plea left his lips, "...please..."

"I see terror in your eyes, Optimus..."

A sharp retort burned on Optimus' glossa, but he bit it back. His position didn't allow for arguing. He was afraid...did he put too much faith in Megatron? Would Megatron really damn himself to a lonely existence ending in the extinction of all Cybertronians just to say he won their war?

The light in Megatron's eyes darkened.

Optimus lost his grip.