Board Thread:Spoilers!/@comment-24304025-20150202171011/@comment-5106672-20150413162146

I think her pendant is a one-shot. It absorbed and amplified her magic (in fact she was powerless when Regina took it from her) and provided her with an escape plan in case of attempted murder, but after that she still had her powers while not being in possession of it. I guess when she was almost-killed she was simply reset to her pre-pendant state, a sorceress with strong powers but who is now killable.