Disclaimer: I own none of these characters nor is Supernatural my intellectual property. I write this for fun.

Castiel stepped into the unwarded warehouse, looking around the open space. His eyes came to rest on the thin figure of Fate, who stood in the midst of the room.

"Hello, Castiel," she said. "I was warned that you were going to kill me."

Castiel stepped forward slowly, keeping the blade behind his back. He noted that Fate was bound within an Enochian pentagram, her ability to flee disabled. "If I kill you, the world will continue on its current path," he said.

Fate sighed. "You're making a mistake."

"No. No more angels will die for the cause of the apocalypse. The world is better this way."

"Already, more than three thousand have died because of Sam Winchester's death in 1983. The collateral damage is huge and will only continue to grow. It's a snowball rolling downhill, Castiel. Soon, because of your petty cause, millions will be dead on earth." Fate shook her head. "If you still think it's right, you can go ahead and stab me with that toothpick and call it justice, but the fact is that it's not and you know it."

"You're wrong." Thunder clapped outside, and Castiel let his true form shine through like a beacon of light from his eyes. His wings flapped behind him and he raised the blade. "You have to die."

Fate set her jaw. "Castiel, you are misguided," she said, a tinge of desperation forming in her voice. "This is not the way it is supposed to be."

"And who dictates that? God?" Castiel scoffed. "I watched the other angels in my garrison die in Hell while we waged war to rescue Dean Winchester. I watched Uriel betray me, and Zachariah trick me. My brother Michael fell into the depths of Hell with Lucifer himself. The apocalypse nearly rent this world in two, and for what? Heaven was nearly destroyed by the chaos. The angels fell into anarchy and disarray. I must kill you. It is the right thing to do." He walked forward, preparing to swing the blade into Fate's flesh. She cowered as he let the knife fall.

Metal clanged against metal. Balthazar appeared in front of Castiel, blocking the knife with his angelic blade. "Not so fast, brother," he grunted, pushing back his strike.

Castiel retaliated in fury, lashing out with an angry blow. Balthazar sidestepped and destroyed the pentagram with a wave of his hand. "Anna!" Castiel called.

The angel appeared behind Fate and grabbed her before she could escape. Balthazar lunged at Castiel, slicing his arm with his weapon. Castiel reeled back. "Balthazar, I will kill you if you do not stop," he growled.

"So be it," replied his brother. "I'm doing the right thing."

Castiel saw Fate squirming out of Anna's grip. He pulled his angel blade out of his coat in his left hand and threw the Fate blade toward Anna while blocking Balthazar's next swipe. "Kill her!" he shouted, turning to deal with Balthazar. But the next thing he heard was Anna's hoarse scream; he turned and stared in shock as Fate plunged the heavenly blade into Anna's heart.

Anna's eyes blazed white and burned as she fell to the ground, the outline of her wings imprinted on the floor of the warehouse. "No!" Castiel shouted. But before he could run toward Fate, Balthazar snatched him up in a vise grip, with a blade to his throat.

"It's over, Castiel," he said.