Something about Castiel seemed off ever since returning from purgatory. He’d been avoiding you and the Winchesters, hunting on his own. You still didn’t know how he even got out. Any attempts to question him just lead to dead ends. Which was strange because Castiel was never one to lie to you or keep secrets from you. You two had always been close and then distance now between you almost seemed unnerving.

After discovering the demons were searching for the angel tablet, Castiel accompanies you and the Winchesters to help find it. You two split off from Sam and Dean while exploring the crypt in which the tablet was located. The box it's hidden in is warded against angels, so you crack it open, retrieving the tablet. He holds out his hand. "Good, hand it to me and I'll take it to heaven."

That didn't seem right, the angels shouldn't be keeping this kind of information. You grip the tablet tighter, something in you telling you he couldn't be trusted. After refusing to give it to him, Castiel snaps. Slipping his angel blade from his coat pocket to his hand as he approaches you with malice. Suddenly attacking you, his gaze cold and distant like he’s not fully there. Knocking you to the ground and standing over you. Staying silent, almost like a machine programmed for a single purpose, to kill you.