Board Thread:Show-Related Questions and Answers/@comment-8345449-20151204052326/@comment-25926288-20151204132825

Well, they didn't plan that far.

But in-show, Zelena's body was destroyed, but her life force left and combined with her magic and made her a new body.

Exclaibur cuts immortal ties, between the life force (or soul) and the body. So, it makes sense that Zelena's life force fled and joined her magic just poofing up a body that is inhabital. Plus, her pendat was sort of like a horcux or something.