Dean moved the wheelchair closer to the deck railing, locked the wheels, rested his good arm on top of the rails and dropped his head onto it "Before you ask, I didn't say anything because I didn't really know until I started reading the translations."

"I..damn it Dean!" He looked out across the lake and tried to find some way to use the still, quiet night to calm down but found he couldn't stay still. All the things he wanted to say but knew he shouldn't yet drove him to start pacing; the sound of his boots on the wood echoed across the deck. "Keep talking."

"When I fought Cain, I stabbed him with the Blade, I did Sam I swear. He dropped and I should have known when lights didn't shoot from his body and there was a distinct lack of hurricane force wind like when I took out Abaddon that something wasn't right. I just...I wanted it to be over. He hit the floor, and something in me changed, the Mark glowed and I felt this rush of power, of something. I thought it was just the Mark reacting to Cain's presence, then a few days later it started."

"What did?"

Dean's reply was so soft he barely heard it, "The other voice, the feelings. The hate."

He stopped pacing and felt his nails digging into his palms from the force he was using to clench his fists. "You were hearing voices and you didn't think that was important to mention?" If these beams in front of me weren't the size of tree trunks I'd punch them, I really would.

"Just let me get through this without the commentary Sam, please." It wasn't the words that throttled down his frustration, it was the tone. He looked away from the imposing outer wall of Oliver's house and saw Dean wiping his eyes along his arm looking absolutely defeated and lost.

"Sorry," he sat back down but couldn't quite bring himself to offer a comforting gesture, like he would have years ago.

"It, Cain, whatever, it came and went. It wasn't all the time but little by little I noticed things. The whole urge to beat the living crap out of people I'd sort of gotten used to but this was different. Things you would do would start to irritate me, I'd write it off as stress, needing to get back on the road, whatever. I'd start having dreams of picking fights with you but I figured it was just a new variation on an old dream. When we go on hunts I'd start finding myself wanting to get away from you, get out of the room, shoot holes in all your theories. I'd have passing thoughts that you hated me, I'd dismiss it, it be worse the next time. It didn't happen all at once Sam, you have to believe me. It's not like I woke up one morning hating you. It just kept building."

"Then I shot you..."

Dean's head moved in a slow nod, "Yeah, when I woke up after surgery and you were standing over me...well. Let's just say it's a good thing I was still drugged up. Even now, knowing what's it's trying to do I can't stand to look at you, hear your voice. I'm barely keeping it together sitting here talking to you. I don't think Cain is dead, I mean it's not like he and I are having extended conversations but what he told me Sam, all of it...I denied it, said it wouldn't happen but now. Now I think it could. Maybe it's not Cain exactly maybe it's just the curse growing stronger because I stabbed him with the First Blade, maybe that just transfers his essence from one body to the next. I don't know."

"Dean? What did he say? You never told me he said anything."

He lifted his head off his arm just enough so that Sam could see his face and when he did his first impulse was to get as far away from Dean as possible. "He said I'd kill Crowley, Cas then you. That I was living his life in reverse, that he and I had the same type of reckless courage which is why he gave me the Mark. When I took it on he told me that we were a lot alike, I'm starting to see why." He clenched his jaw, closed his eyes and looked away again. "Damn it."

The last few months started to shift in Sam's mind, far from not fighting Dean had been struggling every minute of it, struggling against doing the one thing he'd never thought he be able to do. Kill his brother. A lifetime of protecting him was being turned against Dean, inch by inch, minute by minute and what they'd found out in the last few days instead of easing that burden had merely confirmed Dean's worst fears. The boiling cauldron of frustration he'd been feeling dissipated, silenced by his own memories of what the demon blood did to him, those memories and what he knew Dean was fighting against added new layers to the deep well of respect he'd always had for him. There was no hesitation when he reached out and placed his hand on Dean's back. He felt Dean tense when he touched him so he dropped his hand away, realizing that the contact was only making Dean's fight harder and he hoped the words would be enough, "How can I help?"

"You can't do anything more than you're already doing. Listen, you asked me for one last fight." He took a deep breath and managed to make eye contact again, but Sam could see how hard it was, "I will not roll over and play dead for Lucifer or anyone else. We either fix this or end me." Then, as if putting his hand in a raging fire he reached out and latched onto Sam's shoulder. He managed to keep it there for a few seconds before Sam saw the hate grow in his eyes. "One more fight Sam, that's all I have left. Let's make it count." His lips twisted into a snarl laced grimace as he removed his hand, unlocked the wheels on the chair and spun away from him. "Get back inside. Leave the door open. I need a few minutes."

"Sure, all right." As much as he didn't want to leave him alone he knew that being as far away at that moment was the only way he could help him. He paused before he was completely inside again, "I'll have someone bring you dinner."

"Thanks."

He didn't make it more than three steps before he turned back around and took a long look at Dean. He was sitting in profile to the window, he saw the slight hunch forward in Dean's shoulders, the stress lines on his face, the circles under his eyes from lack of sleep. He was staring out into the moon lit blackness beyond the pools of light from the house that settled onto the deck, eyes unfocused as he concentrated on the battleground in his mind and heart. As he watched, his shoulders inched back to how he usually carried them, he sat up straighter and his eyes came back into focus while his head turned back towards the house. Their eyes met and Dean gave him a slight nod which he returned before looking back towards the interior of the house. Dig and Oliver were sitting across on a couch across the room facing the glass door and looked up at him, a myriad of questions in their eyes which he had no answers for.

"When dinner's done can one of you guys take Dean some?"

"Sure," Oliver said.

"Thanks, I need to talk to Cas. Be back in a few." He made it back to the media room and sat next to Cas. "We need to talk.."

"Dean's realized that Cain's essence is trying to take him over and he's almost entirely consumed by hate for you." Cas stated in a slightly preoccupied voice as his eyes rapidly jumped from screen to screen.

"Or you could just tell me everything I just found out, that works too. I take it it's translated more things."

"Yes and no, I'm reading ahead of the program."

"And?" Cas didn't answer, "Cas!"

"Oh, sorry." Cas apologized as he turned away from the screens, "It's fascinating reading, albeit it highly disturbing."

"What is?"

"Well this League of Assassins dates back thousands of years, most of the references regarding the Mark of Cain are from documents that discuss them as well. It seems the League has or perhaps had a rather mystical arm that tracked Cain far more thoroughly then we did. They originally saw him as sort of a patron demon so to speak, being the Father of Murder. They used to offer pairs of brothers to him once a generation as a sacrifice."

"What? Nyssa made it sound like they had fought against the people that bore the Mark."

"They did, but that was much later," Cas said as he leaned farther back in his chair and focused his eyes on the wall behind Sam. "There was some sort of upheaval within the League, the details of which are scarce, but they turned away from the mystical path and became much more grounded in the physical world. The ritual she spoke of was used to try to save some of the last pairs of brothers the mystics offered up. It was then used a few more times after that when the League came across people who weren't fully within the Mark's grasp."

"Does it work?" He wasn't all that interested in the history of the League and wanted to push the angel to get to the point.

Cas's blue eyes moved away from the wall back to him, and he knew he wouldn't like the answer Cas had for him.

"In a small percentage of the cases, from what I can tell, yes."

"And when it doesn't?"

"Both brothers ended up dead. The Lost One killed his brother and the League managed to kill the Lost One, beheading him usually. Then they'd salt and burn the corpse after performing a rather extensive purification ritual to make sure he wouldn't return. The League usually lost several members to the Lost One before killing him."

Well, can't say I'm surprised, Nyssa hinted at that, so did what we found earlier. Can we do this? He said he only has one fight left in him, it sounds like it's a fair chance that may be all that's left in me as well. Guess we better make sure it's a good one then.

"Have you pieced the ritual together yet?"

Cas shook his head, "Not entirely. There are some pieces that are similar enough to other rituals that we can fill in some blanks. On the positive side it won't take the full week to perform."

"A week? What the hell kind of ritual requires that?"

A slight grin manifested on Cas's face, "They spent several days praying for divine guidance and protection."

He felt a small grin break out on his face as well, "Yeah, think we already have that covered."

Cas's grin faded almost immediately though, "She was not wrong about it requiring pain and blood though. Here, look." The angel moved aside and pointed at the middle screen, there was a document on it, not scrolling websites. "I've been piecing it together.

If he thought things were bad before, he'd been wrong. "We have to call forth the darkness? We're basically summoning what's left of Cain to take over Dean? Hell no!"

"It all boils down to choice Sam, it always has and always will," Cas sighed.

His fist hit the top of the desk, "How many damn times are we going to have to make the same choice?"

"I don't know Sam, I don't."