Author's Note
the wolf in the picture is my OC in this story. No negative comments and I hope you enjoy 
Creature summon
Some time passed after defeating nightmare moon and Princess Celestia had a vision. Powerful enemies were to appear in Equestria soon. She couldn't see who they were but she knew that she would need help defeating them. Her sister Luna also said something that was troubling. Stars were starting to disappear and the trail was heading to Equestria. So she sent twilight a message.
"My dear Twilight,
Powerful foes are soon to appear in Equestria. I fear we cannot defeat them without help. Please bring you and your friends to canterlot castle to meet me for a special assignment.
Sincerely, Princess Celestia."
Soon Twilight sends a message back.
"Dear Celestia,
I will be there as soon as possible! You can count on me.
Your faithful student, Twilight Sparkle."
the next day...
"Sorry I couldn't come sooner Princess. I brought everypony as you asked."
"So what's our mission? Are we going to beat up some bad guys or what?" Rainbow Dash said while doing practice punches.
"Hopefully it won't come to that. Come with me everypony." Celestia leads them to a room lined up with guards and princess Luna waiting. "Now come twilight. I want you to use this spell." Celestia gives twilight a paper.
"A-are you sure princess? This spell is too powerful for me to do on my own and the potential consequences of the outcome..."
"Don't worry twilight. Luna and I will supply you with the magic to pull this off. Now, let's start okay?" Twilight nods and begins working on the spell. Everyone falls silent as a circle forms in the middle of the room. Soon it fills with magic and begins swirling.
Twilight grunts as she tries her best to concentrate and the two alicorns supply a steady amount of magic. Soon the portal widens and a big creature falls through and smashes into the ground which causes the sound of glass shattering to ring out.
Almost everypony winces when the creature hits the ground on it's back and begins gasping for air. They watch it unsure what to do about this as they look at it. It's covered in white fur and has golden eyes. It looks like a timber wolf. Another notable feature is the star on the back of it's neck that seems to be constantly changing color.
The guards close the distance while it tries to regain it's breath. They keep their weapons pointed at it until it takes a deep breath and sits up. One of the guards accidentally poke the side of it and in a reflexive move, wings unfold from it's side and knock a few guards away.
Everypony is surprised about the wings except for Rarity, who is admiring the colors in the wings and how they sparkle as well as mix perfectly with the pure white color.
"What's thou name creature?" Luna said in a booming voice. It ignores her and focused on the guards surrounding it. Celestia is pondering what to do when it spins in a circle and uses it's tail to knock away the guards surrounding it.
None of them are hurt but they aren't happy either. One of them charges at it. It moves to the side and clotheslines them with it's paw. The said guard is knocked onto their back hard and the wind flies out of their lungs, leaving them gasping for air.
"Alright, my turn!" Rainbow Dash said excitedly. She rushed in.
"Rainbow Dash wait!" Twilight called out. But it was too late. Rainbow dash rushed at the creature at blinding speeds but it simply dodged. Rainbow was surprised but quickly recovered and resumed her attack. None of her attacks landed.
Then rainbow did a speedy kick at it's head. It took the kick like nothing happened. Rainbow gasped as it flung her back. She rushed again but the wolf ducked and bit onto her scruff and then threw her back to the group.
"I got this." Applejack said as she threw her lasso. She managed to get it on one of the paws but no matter how hard she tugged and pulled, the wolf didn't budge.
"How about a stun spell?" Rarity said as she fired a bolt of magic. The most it seemed to do was singe the wolf's fur which elicited a gasp from Rarity. "Oh, darling I'm so sorry! I didn't mean to do that to your beautiful fur!" Rarity then went to try and fix her mistake. When she got close the wolf picked her up by the scruff as well and put her at a distance. It licked the singed fur and it returned to normal. Rarity let out a sigh of relief.
This time the guards attack all at once. It maneuvers around them and dodges elegantly and with minimal movement. It's tail wraps around one of the guards and throws them at the others toppling a few. It's paws seem rather dexterous as it grabs a spear out one of the guards hoofs and bonks them on the head. The said guard is confused. Another managed to stab the wolf but the spear bends and breaks. The sharp spear didn't even leave a scratch.
The wolf responds by staring at them before slamming the guard into the floor and knocking the wind out of them. It stands up and seems like it's getting ready for a huge attack.
"Everypony wait." Celestia orders and so they all stop in their tracks including the wolf. Soon the guard regains their breath and retreats back. "Perhaps we got off on the wrong hoof." Celestia approaches. " I am Princess Celestia. I am one of the rulers of this land as well as one of the ones to summon you. May I know your name?"
It looks down for a moment before turning back to Celestia. There was a momentary pause. "Of course." The wolf responds in a soft and smooth voice. "I'm Star Glitcher." It seemed like the fight that occured was absolutely unnecessary since Star wasn't showing any hostility even after the events that occured.
Author's Note
Sorry this took so long to release and that its short. I've been busy. Enjoy
Sanctuary
The moon rose over Equestria and the ponies all went to sleep. All except Luna of course. She had felt a strange magic pulse wave through the entire castle and began to investigate. She searched but couldn't pinpoint the source. With a sigh she gave up and went to the balcony where she saw Star with a few new wings. Three light blue crystals and three black crystals forming a saw on her back, spinning at a steady pace. She was staring intently at the sky.
"What does thou see?"
"Unrelenting beauty of the Cosmos. But, some of the key parts are missing." Star says with a frown.
"Thou are correct. The stars have been disappearing. It worries us, but we are glad to have somepony else enjoy the night." She then felt the magic pulse emanate from Star. "So it's thou releasing that magic?"
"Yes. Also there's no need to be formal. Try and relax." She smiled.
"R-right... It's a little hard for us- I mean me. Also what is that magic you're using?"
"You'll get used to it, and its a form. I call it Omega. But I must admit there are few forms of mine that retain my personality. This just happens to be one. Sort of." There was a bit of an awkward silence between the two before another star vanished from the sky. She gave Star a glance and didn't detect any magic used. But she saw the wings spin slow for a few seconds before speeding back up. "Truly saddening."
"Do you know what could be causing this?" She asked worried.
"Collapsing Star." Luna didn't know what to make of that answer or the tone that was given. "I'll be back."
"Wher- What are you doing?!" The princess yelled concerned as Star climbed the rails. Her former wings were gone and the crystals were the only thing on her body. She jumped down and the princess watched as she plummeted before leaving a trail of light and vanishing.
Twilight gasped when she saw the ursa major. She had dealt with the ursa minor but she knew she couldn't currently handle it. She was tired. She tried to use her magic against it to no effect. Everypony tried something again and failed. They watched as the major raised its paw to crush them with and closed their eyes. After a bit, they opened them to see large spike pillars protecting them. The Ursa Major retracted a bit. Twilight turned around and saw Star with 3 white and three grey shards. "Star?"
Star flies up and holds out a paw. Sanctuary. Relax. The air pulsed with a magic that made everypony feel relaxed and at ease. The bear shook their head before taking a swipe at Star. Twilight didn't react in time but the bears paw bounced off an 8 pointed star shaped field. Calm down. Relax. Go home. Rest. With each word, the air pulsed with magic making every living creature that heard obey what's being said, save for Twilight who managed to resist. Star floated back to the ground and the wings shattered.
"Are you okay?" Twilight asked the now panting Star Glitcher as she pat her back.
"Yeah. I can't use that form too much. Makes DE with the users."
"DE?"
"Death effect. Don't worry though. It doesn't effect me."
"Star? Are there more of your kind?"
