Board Thread:Show-Related Questions and Answers/@comment-26116863-20151117024202/@comment-25926288-20151117152717

Let's just say that magic in Once has arbitrary rules that only that work for the plot.

I will claim we don't know what the price to pay in order to save both. But it doesn't make sense. Excalibur was forged to get rid of Merlin's magic and immortality and Nimue knew it could do the same to her. So, in theory, Emma should have just used excalibur to rid herself and Hook of immortality without killing either of them.

Merlin made the sword to rid him og the HG magic and immortality, not to kill himself.