She gets stronger the more enchantments you have and lets you draw off the first one you cast each turn
The seven-mana version will be the surprise factor
There are a few options in this set, such as Lion Sash, that do feel as though they'll be powerful in Standard, Modern and beyond
However with the release of Amonkhet those shenanigans were nerfed by a streamlining of the rules which you can read about here: In short, any split card sitting in your hand, library, graveyard or exile holds a converted mana cost (CMC) equal to the casting cost of both halves of the card combined
After investing into the cards, which ones are the best for your next casual night
That said, Beorn is more of a finisher than a starter, so might just end up in the 99 instead