Lena has a lot of built up anger. This doesn't make her evil. She finally has to pick if she is a dark or light caster.
In my eyes I like to see Luna as a Light caster. She raises her self into the sun far away from everyone. She is sick of people treating he as if she is nothing. Luna is a good person, even though people pick on her. She finds it deep down she must be good, she is a natural, The strongest of all casters. Why would she plague the earth with evil?
LUNA FINALLY PICKS! She reaches her best form.
LET THERE BE LIGHT!!!