Princess Luna was a female Alicorn pony, the younger sister of Princess Celestia and former co-ruler of Equestria.
Apperance
Princess Luna is a dark blue filly Alicorn with dark blue-purple hooves. She has a shiny short mane with very light azure. She's got short bangs on her right side and her hair continues on the side. Her eyes are moderate cyan, she has maastricht blue eyebrows. Her wings and feathers have the same color as her body.
Her Cutie Mark is a moon and around it are black spots
History
Princess Luna and her older sister Princess Celestia grew up as fillies in Skyros where they also knew Opaline Arcana, but later they were sent to rule Equestria.
The two princesses were later asked to rule Equestria by their teacher Star Swirl the Bearded to help unite all the pony races. Which was a dream come true as they both always dreamed of ruling one day. When they accept this invitation, however, they are still blank flanks because Alicorns age differently than other ponies and because duties with the moon and sun were still under the control of King Bullion and Princess Platinum.
Later on, Star Swirl asks the princesses to take control of the moon and sun and so, Luna and Celestia go to do a moonset and sunrise. When they succeed, Luna has received her Cutie Mark of the moon and Celestia of the sun.
Personality
Princess Luna was introverted, empathetic, and compassionate. She was also known to have a bit of a temper. Before her banishment to the moon, she was craving for approval and felt jealous of her sister's attention. As a result, she transformed into Nightmare Moon.
As Nightmare Moon, she was overconfident in herself as well as spiteful and power hungry. After being transformed back to normal, she held a lot of remorse and self-hatred stemming from her previous actions for a while but ultimately proved herself a changed pony.
As a filly displayed in Opaline's flashback, Luna was shown to be lively and playful. Although, she was also depicted as prideful as well as displaying a dismissive and elitist attitude towards Opaline. However, that negative depiction of Luna is questionable at best as it was only shown from Opaline's perspective.
Media
My Little Pony: Make Your Mark
Chapter 4
In Sunny Side Up, Princess Luna was seen alongside her sister Princess Celestia in Opaline's origin. It showed how they grew up in Skyros and how Opaline tried to be a 'friend' them, but they turned away and refused her request, causing Opaline to become resentful and jealous of her and Celestia.
My Little Pony: Tell Your Tale
Season 2
In Misty-rious New Room, Princess Luna is pictured of her and Princess Celestia defeating Discord and turning him into stone with the Elements of Harmony. Princess Luna's evil counterpart, Nightmare Moon is being defeated by the Mane 6 using the Elements of Harmony.
Trivia
- In Spanish and Italian the word "Luna" means moon.
- Her bad form is legend to this day. This is implied when Sunny Starscout, in the Nightmare Night Party episode of Tell Your Tale, disguised herself as Nightmare Moon.