"Dean Winchester. It's been a while." Cain surveyed the sixty-odd demons surrounding him as though taking in an uninteresting display of overpriced corn.
"Thought you'd given up fighting," Dean returned. He held himself on the cusp of battle, ready at a moment's notice to sink into a crouch and lunge with biting blade.
"It seems I was simply waiting for the right cause."
Cain ambled closer. Dean tightened his already firm grip on the Blade.
"I'll have to ask you to order your Knight to stop that spell, Dean," Cain said calmly, gesturing to Michelle. Only his eyes carried the unspoken threat across the dark grass.
"Ah, I dunno," Dean returned, half-glancing back at the widening crack. "Nothing can stop her when she gets like this. Ever seen A Beautiful Mind? Not even close."
Cain smiled benignly. "Nonetheless, Dean." His voice hardened suddenly, all joviality evapourated. "Make her stop or I will. Your choice."
Clenching his jaw, Dean half-turned to Michelle and spoke low enough so that Cain wouldn't hear. "Whisper it. And stand still."
Michelle got to her feet and stood, her mouth slightly open and, so faintly that even Dean could hardly detect it, moving. Dean wondered bizarrely if she'd ever taken ventriloquist lessons.
"It took me a while to find you," Cain began conversationally as Dean turned to face him. "Congratulations."
"Think how much harder it would've been if I was hiding."
"Oh." Cain came to a halt several feet before Dean, out of range of the Blade. "You don't call what you've been doing hiding?"
Dean grinned. "I call it conquering."
Glancing down at his feet, Cain let out a low, humourless chuckle. When his gaze returned to Dean's, it was serious and solemn. "I see I was wrong about you, Dean. And for that I am so sorry."
Dean snorted. "Wrong? How were you wrong! I've been a demon for a year and look what I've done! I've taken Hell, I've brought the Knights back, I'm about to take the power of the Veil! I've killed thousands!"
"Exactly."
Dean frowned.
"The only reason I agreed to give you the Mark, Dean," Cain continued, "is because I mistakenly thought you could control it. I thought you were stronger than I was. After all, you saved your brother."
Dean's frown deepened dangerously. "Don't you talk about him," he spat.
"No," Cain continued as though there had been no interruption, his tone thoughtful. "I killed my brother and fell to the Mark for centuries. You saved yours and fell further."
"Don't you talk about Sam!"
"Maybe it's because of him you've gone so far. Trying to severe the ties? I wonder, Dean Winchester, how much of what you've done has been, ultimately, to protect your brother."
"What I've done I've done for me!" Dean roared, spit flying from his mouth. "I did it because I could and because I'm damn good at it! I did it because this" – he gestured to the gathered demons and the shimmering, howling crack in the night – "is who I am!"
Cain was shaking his head slowly, a small smile on his lips. The sight enraged Dean further, and his rage powered the Blade's unsated thirst.
"I'm gonna say this once, Cain! I'm gonna give you fair warning: turn back. Leave now and I'll let you leave. You do not want to test me."
Cain's eyebrows rose a moment before crashing down in a fierce scowl. So fast he must have teleported, he was in front of Dean, one hand clenched around his throat, lifting him into the air.
"Think who you're talking to, boy," he spat, his hand halting Dean's arm as he attempted to shove the First Blade into the old demon's side. "I was the first murderer! Everything you've done – all that killing, all that destroying – it is nothing" – Dean's demons started forward, trying to surround Cain; he sent them flying back a hundred feet without blinking – "nothing compared to what I did! To what I am! You think a bullet is the most terrifying force to exist? That all should quail before its power? I was the first bullet, boy! I was the first gun!"
Dean choked, gasping for breath. Unable to break Cain's hold on his throat, he brought his leg up hard, kneeing the first murderer in the groin.
Cain dropped him with a snarl, recovering impossibly fast and throwing a merciless punch at Dean's jaw. Dean took it, using the stinging momentum to whirl around and slice a line of red across Cain's upper arm.
The First Blade shuddered deliciously at the contact.
Cain's eyes widened in shock and – fear? Dean's lips curled into a vicious snarl.
He lunged again, thrusting with the Blade, aiming for Cain's heart, but the old demon was expecting it. He blocked the blow, grabbing Dean's wrist and wrenching it backwards. Dean cried out as he heard and felt a loud snap.
Before Cain could grab the Blade, Dean disappeared, returning a split-second later behind the old demon and landing a solid punch to his kidneys with his uninjured hand. Cain roared in defiance, whirling around and continuing his attack in earnest, as the souls' howls grew louder and more piercing behind them.
As they traded blow after blow, each parrying and dodging the other's, Cain sent demon after demon that ran to Dean's aid hurtling back in a flash of ruby red. He never so much as broke rhythm.
Blood blossomed over Dean's eye. He felt a rib crack and his abdomen clench against the pain of Cain's boot. As blood from his lip dribbled into his mouth, Dean smiled, flicking his tongue out to taste it. Finally. A challenge.
Dean rammed the sole of his thick boot into the centre of Cain's chest, sending him stumbling back a step. It was enough: focusing intently, Dean brought both his hands together over the First Blade's hilt and called the lightning. Light shot from the tip of the Blade, so bright it seemed to rend the night in half, screeching through the air right at Cain's unprotected chest.
A split second before Cain was blotted out by the brightness, Dean saw the old demon's lips curl back in a smug smile.
The lightning made contact with a deafening crack, sending a concussion through the air like thunder, slamming into Dean and knocking him back a step. He held fast, holding the old knife steady as he waited for the resistance that was Cain to be obliterated into a fine dust.
Instead, Dean felt the Blade shudder. Glancing down at it, Dean saw it flinch in his hands again as a shock of white light ran like a ring up the shaft of lightning and passed over the Blade, then shuddered painfully up his arms. Gritting his teeth, he threw his weight forward into the assault, taking a step closer to Cain.
It was no good. The lightning was dimming. Dean could see Cain's shadowy silhouette through the shield of burning light. Cain's had was raised, his Mark glowing like a firework. He was absorbing the lightning.
For the second time in the same month, Dean Winchester felt fear tingle inside him.
He just had time to make out Cain's shadowy figure extend his arm as though pushing open a door before the lightning turned back and engulfed him.
Every nerve seared with pain as he was thrown backwards. The world was white and screaming so hard it hurt Dean's ears. It took him a moment to realise the screaming was coming from his own mouth.
He landed with a bone-jarring thud on the hard ground as the whiteness vanished. Darkness loomed around him as he rolled onto his side, coughing, blinking away the searing aftereffects of the lightning. His body burned. He tasted blood and spat, pressing his face into the blissfully cool grass.
He felt the rhythmical thuds of approaching footsteps. A hand curled around the collar of his jacket and pulled him to his feet. His fingers closed around empty air and he reached out with his mind for the First Blade. He could feel it, it was so close, but it was locked in a grip stronger than a cursebox. Struggling to support his own weight, Dean blinked the image of the first murderer's face into focus. Cain's grip shifted from his collar to hold him up by a fistful of jacket. Dean felt the blood-warmed, razor-sharp edge of the First Blade press gently against his exposed throat.
"You didn't really think you'd learned all my tricks, did you, Dean? The Blade and I were one for centuries. You've barely scratched the surface of its power. Of its secrets."
Coughing, Dean saw a shadowy figure standing beside the shimmering crack of the Veil throw their arms out to him, as though reaching out to save him. The crack closed abruptly and the energy it had gathered came thundering into Cain's back with a long, high, piercing screech.
Without showing any emotion, Cain whipped his blade-wielding arm back, aiming its point at the oncoming force. As the howling energy reached the point of the First Blade, it crashed like a wave on the invisible wall of Cain's power, rumbling off in a shockwave that shook the ground.
The Blade's point turned to the figure standing over the useless sigil.
Dean's eyes widened. He gasped for air, desperate to call out.
"Mi-chelle!" He fought against Cain's grip. "RUN!"
The figure disappeared a split-second before a shock of red-tinged lightning tore through it.
Cain turned to face Dean. His eyes were black. When he spoke, it was in a voice as low and powerful as thunder.
"Enough, my son!"