A/N: This is my first Supernatural fanfiction. I had originally intended for it to be a one-shot, but it ended up being novella length, so I'll be posting it in parts.
Sam could see everything Lucifer did. He could feel everything. And it broke his heart because it now felt like he was beating his brother to death. He felt his fist connect with Dean's face over, and over, and over, and over again. He heard him calling out for him as he took his beating, not fighting back so as to not harm his brother's body. Sam could see Dean's swollen, bleeding face. This had to stop!
Lucifer was doing more than harming Dean. He was fighting Sam, who was trying tooth and nail to get control back. But he was tired. No, he couldn't give up. Dean's battered face made him want to scream. This hurt him more than any physical pain he'd ever felt.
And then, Lucifer faltered. Was it because Sam was thinking about Dean?
Desperately, Sam grabbed at the possible weapon presented to him. He went through memory after memory of Dean. All the moments Dean had his back, all the moments they laughed together, hunted together, hugged. All they'd ever done was look out for each other. He showed Lucifer everything in one large burst of emotions.
Yes! he thought when control shifted over to him.
Lucifer was slamming himself against the wall he'd erected in his mind, trying to get free. The fight of holding him back exhausted Sam so much that he didn't even have the energy to cry over Dean's wounded state, but he was able to talk. He had to reassure his brother. "It's okay, Dean. It's gonna be okay. I've got him."
With great difficulty he dropped the rings he and Dean had acquired from the four Horsemen onto the yellowed and dead grass that covered the ground, and recited the incantation. Lucifer's prison opened, a deep well of blackness. He looked back at Dean as a last goodbye before turning back to the prison, ready to jump in. The wind from the void tore at him, like it was yearning to have Lucifer back in its depths. Like it understood what had to happen.
Just as he was about to jump in, a voice called to him, "Sam!" He turned to look at Michael. "It's not gonna end this way. Step back."
"You're gonna have to make me!" Sam cried. Nothing was going to stop him from completing his task.
"I have to fight my brother, Sam," Michael responded. "Here and now. It's my destiny."
Sam looked at Dean, at his bloodied and swollen face. He could barely recognize his own brother. Lucifer had done this to him, and if he didn't do this, if he didn't go into the prison, the world would burn. So Sam closed his eyes, spread his arms out, and began to fall backwards into the void. Michael reached forward and grabbed his jacket, but not even Michael could stop him now. Sam grabbed his arm, and pulled him down with him. The two of them fell, and Sam was swallowed in darkness.
A/N: For those of you who have been reading my other fanfictions, well, this is partially the reason the updates were delayed. I was working on this and I wanted to finish it before posting it. So sorry about that. And to my other readers who are only being introduced to my writing through this fic, well, I hope you enjoyed it, and there'll be more where that came from.