Board Thread:General Discussion/@comment-24674051-20150420171129/@comment-5106672-20160321182452

It's interesting to note that Zelena had two spells cast on her: the Clover's glamour spell and Ingrid's freezing spell. We don't know yet whether Zelena was actually affected by the freezing spell the first time or just faked it like she did the second time, but if she were then they could have added up. Or maybe Ingrid's spell could have "suspended" (or "frozen", or "hybernated", as you prefer) Zelena's heart-protecting spell on its own. I mean, Ingrid's freezing spells were definitely serious business, given how they suspended the life cycles of the whole Arendelle for a good thirty years even after Ingrid herself had left the land.

So yeah, it's reasonable to think there was a lot of powerful magic interfering back then.