au: lydia kills peter.
"I used powder of wolfsbane from Deaton’s spice cabinet to subdue him. He wasn’t quite unconscious after that, said something about how I couldn’t go through with it, that we had unfinished business to attend to. He got to watch as I drove the knife into his chest. I buried the body at the ice rink—Boyd didn’t exactly say that it was okay, but he did leave me the keys to the zamboni, and, well, I think that’s permission enough, don’t you?”
"Are you telling me that you killed an alpha werewolf? That you killed Peter Hale?"
Lydia smiles. ”What, like it’s hard?”