Oh, poor sweet Yggdrasil. I almost forgot her. I'm so sorry baby. It's not her fault. She really just doesn't have that memorable a design compared to a lot of the other Primal Beasts, or even to some of the characters. She's a mute anime girl with a couple leaves on her head. She's also the last of the initial Primal Beasts, rounding out their representations of the four main elements of GBF's setting. Her backstory with Rosetta is really cute, but other than that, I've always found Yggdrasil to be a little forgettable.
Her Omega form is also just anime girl with leaves on her head, though now she has an overflowing and richly detailed skirt that's far bigger than her actual body. An improvement, to be sure, but she's just not much of a stand out to me. Sorry Yggdrasil. It really kills me to be mean. :(
Final Score: 3/5 Leaves