Board Thread:General Discussion/@comment-25597861-20150210170713/@comment-25926288-20150210184430

It is likely a small oversight. However, Maleficent may be a different type of being. She seems to be a magical being. Unlike normal witches and elementals (Ingrid, Elsa, Rumple), she has many forms and made up of her magic. Actually, she might be similar to elemantals, in which they are magic goo. Maleficent turns into a dragon, a flock of birds, and possibly other forms that make her up. The spell likely sustains her form changing and the way she can be killed is unique, besides heart ripping, shadow snatching, etc.

Normal witches like Regina, Zelena, Cora, Jafar, and Amara, simply channels magic, but aren't a magical being.