She herself is clearly Nightmare Moon. She just got blinded by her own anger and jealousy and power. It was only when she was brought to her lowest that she became humble and realised what she had become
Whether Luna was possessed during her time as Nightmare Moon, or if she was fully in control and lashing out, would be the subject of much debate for the next thousand years.
I don’t know the answer myself, but I’m happy to have her now, the way she is.
Edited
It was thou who reslesed the elements of harmony upon us and took away our dark powers. I agree 100%
Or would that not help?
Twilight’s lectures tend to be intense.
Let’s settle on they learned and fainted from too much.
The gossiping mares
faintlearn.FTFY
It’s super effective!
The gossiping mares faint.
Edited because: Typo
I don’t know the answer myself, but I’m happy to have her now, the way she is.