Earth
Elphaba was a creature of the earth. Her skin was the color of the grass, shrubs, and leaves.
When she was younger she used to rub sand and dirt on her face, saying it was makeup. And in a way, it was.
The Grimmerie was ancient and earthy; many of its spells had something to do with changing things. Magic was as old as the earth, or at least that's what she learned at Shiz.
She loved the earth so, she became a witch—witches were said to be servants of earth…
She learned from the earth. She learned empathy and compassion from the silent animals she saw, scurrying around. She learned how to clean herself with herbal oils.
Elphaba was a creature of the earth...