Many has heard of the tale of Twilight Sparkle becoming an Green Lantern and fighting off Trixie who join the Sinestro's Corps. There was also tales that Princess Luna still has parts of Nightmare Moon in her. But what no pony knew, Trixie was not the first pony to join the Sinestro's Corps, Princess Luna was. Luna sat on her throne and took out the ring she kept hidden in her mane. Like all yellow rings, the symbol match the corps that it belongs too. Luna was afraid of the ring at first, but now had grow use to it. Luna play with her ring in her magic as she remember the day it first appear before her.
Flashback
Luna was upset, it was her first Nightmare Night and she was trying to get ponies to see that she was no longer Nightmare Moon. For an while it was working, thanks to Twilight Sparkle and friends. However when an scare went wrong, Luna became upset and remove Nightmare Night. She later found that it was an way to enjoy dressing up and not even worry about the "Mare in the Moon". Luna sat on the ground after getting away from Twilight and stomp her hoof in anger.
"Is that how Ponies treat us? After an 1,000 years and they still see us as Nightmare Moon? I will not stand for it!" She yell before thinking about Twilight.
"Lady Twilight was the only one not scare of me when I arrive. I know she means well, but it appear's I put fears in ever ponies heart when I show up." Luna said sadly and sighed.
Luna look at the ground wondering if coming to Ponyville was an good idea or not. She look up towards the night sky she had cover in her rage and saw something break through. She watch as an yellow light come at her and stop in front of her. Luna look at the ring and saw an symbol that she never seen before. Then she heard an voice inside her head.
"Prince Luna of Equestria, You have the ability to instill great fear. Welcome to the Sinestro Corps."
Before Luna could question on who the Sinestro's Corps are, the ring went on her hoof and soon was cover in an black suit with yellow on her chest in shape of the armor piece, her back hooves had yellow boots and an collar with yellow line are her neck. Her hooves slippers (I not sure what they are call), had also turn yellow. On her front hooves was golden bracelets with one of them the ring on her right hoof. Her wings appear out of the side of the suit. Her mane and tail remain the same. (See cover for an better view)
Luna was able to remove the ring before Twilight found her. Ever since that day, Luna had kept the ring secret from everypony, even from Celestia. Luna was unsure about the ring until she saw Trixie wearing the same ring. She was shock to learn that ring uses fear to scare other and it get more powerful as others remain scare. After Twilight defeated her, Luna train with her ring in secret. She decide not to show anyone her ring. She was afraid that ponies will see her as an member of the Sinestro's Corps and Celestia might banish her again. Many thought the Yellow Lanterns are evil and shouldn't be trusted. Luna look at her ring again then turn to her Lantern. Luna as also heard it oath and knew it was wrong to use fear to bring Justice.
She decide to train with the ring again and put it on. She walk over to her Lantern and place it on the Lantern and said the oath.
"In blackest day, in brightest night, Beware your fears made into light. Let those who try to stop what's right, Burn like his power, Sinestro's might!"
Luna hated that oath. This Sinestro didn't sound like a good...whatever he is...to her. Her Yellow Lantern suit appear on her and flew outside. She flew away from Canterlot to an small clear field that she been using as an training area. Letting the ring read her fear, Luna constructed Nightmare Moon out of yellow energy. Luna lower her ring and look at her former ego. Seeing that form always remind Luna the day she become that. Nightmare Moon look at her and roar. Luna ready herself as it charge at her.
Luna was quick to bring up an yellow shield that had Nightmare Moon ram into. Luna grunt as she try to hold Nightmare Moon back. Her construct held as she started to push back. During her earlier time training with the ring, she could barely hold up an construct for no long then one second. Now that she was using fear from other ponies nightmares (which she hates to do) she was able to hold up to a an full minute. Tonight, she was able to hold back without it cracking. Luna push her former ego away and made an sword construct.
Nightmare Moon swing her horn and Luna block it. The two battle battle sword to horn for an few seconds before Luna let the sword disappear and fire her ring, making an brick wall, slamming into her former self and both of the constructs disappear. Luna sigh as she look at her ring. Fear, that what she had just use. Fear was not the way to do this. But she knew she had to use it. She just hope that one day she can show everypony she not evil any more and is not an member of the Sinestro's Corps. Luna turn to see that it was time to lower the moon. She turn back to Canterlot and flew off. What she didn't know that she was being watch by another member of the Sinestro's Corps.
Luna yawn as Celestia woke her up an few hours after she lower the moon. There was something about an meeting with Twilight. Luna knew well that Twilight was an Green Lantern. As she knew, the Sinestro's Corps and Green Lanterns where not friends. From what she heard, Sinestro was once an Green Lantern before he was kick out of the corps. But Luna was hoping that one day, she can be the first to fight by Twilight side. For now it was about the meeting they we're going to have.
They both step in the throne and saw Twilight there in her Green Lantern suit. She bow to them and they bow back.
"Twilight, my student. What bring you here?" Celestia asked.
I want to to know that I'll be leaving for some time. I don't know how long I will be gone, but I have ask Shining and Cadance to take over." She said.
Luna remember well that both Shining Armor and Princess Cadance join two different Lantern Corps. Shining join the Red Lantern Corps and Cadance join the Star Sapphires Corps. Wondering where Twilight was going, she asked her.
"Where are thee going Twilight?"
"The guardians need me at Oa. Said something about Hal wanting to take me to his planet." Twilight answer.
Luna knew who Hal was. Hal Jordan Green Lantern of the planet call earth. He also one of Twilight teachers on using her ring.
"Have you told your friends?" Celestia asked.
"Yes, they will watch over Equestria while I'm gone as well." Twilight said.
"We wish you luck on your quest." Luna said and bow.
Twilight bow back and took out her lantern. She place her ring on it and said her oath.
"In brightest day, in blackest night, No evil shall escape my sight. Let those who worship evil's might, Beware my power, Green Lantern's Light."
Luna like that oath. She could tell that the oath she has was just an revision of Twilight's oath. Twilight flew off and disappear in the sky. Both Princesses sat sat in their thrones are soon was going about their royal day.
In a few hours, there was another type of meeting this time some ponies wanted to know about Twilight being an Green Lantern. Many ponies wanted to join the same corps, but as Twilight told them, they have to be chosen. There was even some that was wondering about Cadance joining an corps. Not much was talk about that one. Some was a little worry about Shining join the Red Lanterns. True that he was blind with rage, but he now uses it to help. Finally, there was the thing about Trixie.
"So, you really letting her go?" One ask.
"Trixie had no idea what the Corps was. After all we are not alone in the universes." Celestia clear up.
"What about the other three corps? I understand two are helping us, but what about that red one?" The same one asked.
"Shining was blind with rage. From what Twilight has told me, there other corps, But she doesn't know them." Celestia said.
"What do we know about the Sinestro's Corps?" Another asked.
"From what Twilight told us, it a corps that uses fear to bring justice. The founder, who's name is Sinestro, was once an Green Lantern until he was kick out. The corps also uses the weakness of the Green Lanterns." Luna spoke up.
"If the Sinestro's Corps uses fear, then what does the Green Lantern Corps use?" An third ask.
"Willpower." Celestia said.
Luna turn to the side and saw something. Whatever she saw, it move before she could make it out. It did, however, show to wear yellow. Luna decide to go see it and hopefully stop who or whatever it was.
"Sister, there something I must attend to. I'll be back shortly." She said to Celestia.
Celestia was wondering why Luna had to leave, but nods and Luna walk outside. Once Luna was out of the castle, she took the the skies and look around.
"So, you're the member?" She heard.
She turn and saw an creature she didn't realizes, but saw the well familiar symbol of the Sinestro's Corps. She stood ready encase of an attack.
"So tell my, why are you not using fear to bring justice here?" It asked.
"Using one fear is wrong!" Luna said, before noticing what was said.
"Wait, how do you know I'm an member of the same corps as you?" She asked.
"I saw you wearing the Corps uniform last night." It clear up.
Luna was shock to hear that. It knew, she kept it secret and it knew.
"Who are you?" She asked angrily.
"My name is Ran. I been searching the the missing ring for a really long time. It appears that you are the owner." It said.
"Unlike you, I will never follow those corps! I work hard on showing everypony I'm not same mare 1,000 years ago!" Luna said.
"Then, I'll place fear in the ponies." Ran said before putting up an shield to block an beam.
"WE WILL NOT LET YOU DO THIS!" Luna shouted.
After seeing what Trixie did with ponies fears, Luna was not going to let it happen again. No matter if she was an member or not.
