Ruler of the moon, goddess of the tides, and a master of dreams. She ruled with her sister for what seems like eternity in peace. As for her Nightmare arc, nothing changes there. She still becomes envious, envy consumes and transforms her, and she’s banished.
After coming out of her Nightmare Moon form, many things about her were slightly altered. Her once bright and soft fur is now darker and rough, her wings remain bat-like, and a large, veiny black scar extends over her back.
Before, she was much quieter and compliant, passively letting her older sister take the lead on matters of villains and troublemakers, and had an air of calmness and grace about her. Afterwards, she has outbursts of anger and loudness, she’s more vocal on issues brought to her attention, and goes through periods of being very reserved, going days where she wouldn’t speak at all. She finds some ponies still feel uneasy around her, when once they found peace and comfort. It hurts her to know this, but it makes her want to work harder to restore the confidence of her people.
Her relationship with her sister is still strained, but they continue to work through it day by day. They make the effort to keep up appearances of a strong front, but it can be tough. Luna loves her sister though, and wishes to work through her latent anger.
When she re-encountered Chrysalis at Canterlot, they spoke alone very briefly. Luna, against her better judgement, let Chrysalis go. She was relived everything ended up alright, but was disappointed in herself for allowing it to happen. When Chrysalis came for maybe the last time to drop off their daughter, she wasn’t sure what to say, but they left each other on good, perhaps even hopeful terms. She raised Dynasti into adulthood with all the love she could give, hopeful for her daughter to bridge the gap between the changelings and ponies even further than Thorax could.