Board Thread:General Discussion/@comment-24942479-20170426102234/@comment-25926288-20170426103512

Maleficent is continuously alive in one form or another due to Regina placing a spell on the cavern that would sustain her. So, she's like the type of immortal that lives very long, but can be killed.

Kristin Bauer van Straten (the actress) said Maleficent was immortal. Given that Maleficent has aspell book that even Cora uses and doesn't seem to have aged, I think she's going to be very longed lived (she burned a fire for half a lifetime = about forty to fifty years) and if she can replicate that sustenance spell, then she could be immortal.