//------------------------------//
// Exorcism 
// Story: Gloom and Doom 
// by casualbrony10 
//------------------------------//

	The first thing the ponies noticed once they had gotten their bearings in the entrance hall was the numerous bodies of royal guards strewn about haphazardly. All were fully at Gloom's mercy, their wills broken and reduced to incoherent muttering as they stared into space. The band of friends walked down the hall to the throne room, searching for any sign of Celestia or Luna. They didn't have to search long. Luna lay where Gloom struck her down, in the center of the throne room in a puddle of black ooze. 
"Luna!" Twilight yelled as they quickly gathered around the fallen princess.
"Oh no! She's just like every other pony. We're too late." There were tears in Fluttershy's eyes as she spoke. 
"Maybe not, I know that Gloom uses mind magic to do this. It's a long shot, but maybe I can use mind magic to free her," Sunset stepped close to Luna and stared into her eyes. "Everypony stand back, I have no idea what will happen." Sunset entered Luna's mind, and immediately encountered resistance in the form of a wall of shadow. Luna stirred in her trance as Sunset  started trying to break through. 
Gloom sensed a disturbance as somepony tried to steal his prey. Even in the midst of his grand spell Gloom refused to release his most powerful prisoner. Gloom's eyes glowed as he shoved Sunset's mind back. 
Sunset gave a yelp as she suddenly fell back from Luna, feeling as if she was punched. 
"Any luck?" Ranibow asked. Sunset shook her head sadly. 
"Gloom's will is too strong, I'm nowhere near good enough to free her."	
"What about all of us? Is there a way we can help? At the very least Twilight and I can lend our magic," Rarity suggested.
"Mind magic doesn't work that way. It's not a matter of raw power, it's strength of will. You would all need to enter Luna's mind with me and stuff like that took me weeks of practice before I got it right."
"Beg pardon Sunset, but who did you practice on?" Applejack looked a little nervous at the implication that Sunset had entered minds before.
"Just mice and rodents around the castle... oh and don't worry, I didn't do any damage, just in and out to see if I could," Sunset hastily explained when Fluttershy gave her a horrified look.
"It's worth a try, we can't leave Luna like this and we really need her help. I'm a fast learner and Fluttershy has the strongest will I've ever seen," Twilight stepped forward next to Sunset.
"Oh, I'm no stronger than anypony else, really," Fluttershy started to look scared.
"Now is not the time, the stare is proof of the strength of your mind. You can force your will upon others without even knowing what mind magic is. Come on, I won't let anything happen to you, trust me," Sunset gave a comforting smile. With hesitation, Fluttershy took position next to Twilight and Sunset. "Everypony else stand guard while we do this, I don't know how long it will take to free Luna or how deep we will have to go into her mind. Now, both of you clear your mind and quiet your thoughts. Tune out everything around you and focus on the sound of my voice. I order to enter the mind of another you must enter a sort of meditation and trance." A few moments passed as Twilight and Fluttershy focused. "Good, now focus on Luna, picture yourself walking toward her, reaching out to her, eye contact helps, stare into her eyes. Now, I'm going to cast a spell to help but for this to work you must use a little of your own magic. As you reach out to Luna add just a spark of magic into your efforts. Twilight channel a little magic into your horn and focus on Luna, just a little. Fluttershy imagine you are flying, use your pegasus magic and focus on Luna."
After a few minutes of intense concentration something gave. Twilight and Fluttershy found themselves floating in a great void. Sunset was with them and in front of them was a great wall of writhing darkness. A pale blue glow twinkled on the other side, undoubtedly Luna's mind.
"Now, focus on the wall, imagine it breaking, imagine getting to Luna. Push against it, no matter how hard it resists or how much it hurts." The three started fighting Gloom's power. As the duel of minds began the rest of the group stood around the 4 entranced ponies, watching for any signs of danger. The sound of hooves tapping the floor echoed from down the hall. As the ponies turned to look Celestia walked in, or rather, shambled in like a zombie. 
"Princess Celestia! We're so glad to see you're alright! Luna is in a terrible state and we're trying to save her, please help!" Rarity said as she trotted over to the princess. Celestia simply stared at the ponies, her face blank and her eyes gazing into space. The thing possessing her surveyed the possible hosts before it, it would need to leave Celestia soon as it had misjudged how injured Celestia was. It was taking more magic to sustain her crippled body than it could extract from her. Its gaze lingered on 2 alicorns, sensing their magic, but Luna's was already being siphoned off by Gloom, the thing feared that it would be drained as well if it attempted to usurp Gloom's hold. Twilight, however, shined like a beacon in the thing's eyes, so much power packed into such a vulnerable pony. The thing began to advance towards the entranced princess. 
Of all those present, Spike knew Celestia the best, she had practically raised him for the first couple years of his life after Twilight hatched him. He immediately knew something was wrong when Celestia ignored Rarity and began to shamble towards Twilight. 
"Princess Celestia? Are you okay?" He stepped into Celestia's path before a voice suddenly screamed in his mind.
Spike run! Get away from me, this is my body but I'm not in control. Get away before it cuts off my telepat- Celestia's psychic voice was cut off as her possessor isolated her mind, but Spike got the message.
"Everypony get back, that's not Celestia! Somethings controlling her!" Spike yelled. The thing, with the element of surprise lost, dropped all appearances and screeched, rushing towards Twilight. Applejack reacted first, tackling Celestia in the legs and knocking her to the floor. Rainbow and Pinkie then piled onto the possessed princess, pinning her to ground. Celestia twisted out of their grip, shrieking like a banshee as she made a beeline for Twilight. Rarity fired a stunning blast into her side, knocking her across the hall. Celestia recovered and started climbing up the wall like a spider, bile leaking from her mouth as she snarled at the ponies. Rainbow slammed into her and they tumbled to the floor. 
"Sorry princess if you felt that, and get out of her whatever you are!" Rainbow found it very hard to address a body shared by both victim and villain. Despite all the commotion Twilight, Fluttershy, and Sunset still sat in place, staring at Luna, oblivious to the outside world as they sought to free their friend.
In the mindscape, the three ponies pushed as hard as they could against Gloom's power, slowly it started to give as they inched closer to Luna's consciousness. 
NO! Gloom's voice roared at them as the dark pushed back.
"Keep going, you're both doing great, we've almost reached her!" Sunset called words of encouragement to Twilight and Fluttershy as they struggled. Gloom's magic began to fail, he couldn't fight the ponies and continue building his masterpiece around the crystal heart, Luna was too far away for him to maintain his grip. With a snarl, Gloom gave up and redirected his efforts to the heart. The wall of darkness gave completely and the three ponies broke through. Twilight gasped as she was thrown back into the physical world, and right into a battle between her best friends and her mentor, Princess Celestia.
"What the?! What the hay are you doing!?" Twilight yelled in shock.
"Oh don't worry Twilight, Princess Celestia is possessed by some evil force, so we're gonna hold her down and say 'The Power of Harmony compels you' until she's okay," Pinkie said. Twilight stared as she processed it.
"What!?"
"Your friend speaks the truth, I recognize the shadow tainting my sister's aura,"a weak voice said from behind Twilight. She spun around to see Luna, awake at last. The moon princess struggled to stand as she shook off the last of Gloom's influence. "I am in you debt once again Princess Sparkle, now help me free Celestia." Together with Twilight, Rarity, and Sunset, Luna held Celestia down with their magic. Celestia screamed and snarled as she flailed helplessly in the telekinetic grips of the 4 magic users. Luna walked over and leaned in close to her sister, examining her face. "This is grave indeed, somehow a night terror has seized control of my sister."
"What's a night terror?" Rainbow asked.
"A dream demon, much worse than the simple nightmares. Terrors are from the dark beyond that creeps at the far reaches of the dream world, they are very rare, in all my years I have only encountered a handful. It takes very powerful dark magic to allow one into our world and even then they need a physical body. It seems that this one slipped through in the wake of the Gloom creature. I've dealt with them in the dream world before, but I have never seen one fully possess a living pony. I don't know if I can banish it without harming Celestia. Can you use the power of harmony? Such cleansing energy could easily remove the parasite." In answer to Luna's question, Twilight shook her head.
"Gloom did something to us, we can't feel the magic of friendship anymore."
"Are you sure? I can still feel its light within each of you, its very weak, but still there. I once bore 3 of the elements and you cleansed me with their power, if your connection was truly severed I would know. In fact, the rainbow shines brightly in...you?" Luna turned with some confusion to Sunset. "Who is this?"
"I'm Sunset Shimmer, I was once Celestia's student and I became friends with Twilight in the human world."
"Ah, I see, you are the one who tried to steal Twilight's crown. I have seen the letters Twilight writes to my sister, there is no doubt, your connection to harmony is just as strong as the others. What that means I do not know, but perhaps this is what we need. Did the monster put the same enchantment on you that it did on the 6?"
"Now that I think of it, no. Discord saved us before Gloom could even figure out who I was."
"Good, then through you the connection is maintained and can be restored to the others. There isn't much time, the more dark magic builds in Equestria the greater the chance more unwanted visitors will enter our world, and I can feel the Gloom's power growing somewhere far away. Without me or my sister, it no longer wields the power of the sky, but I doubt that will matter with all the magic I feel building to the North. Sunset, I'm sorry to ask so much of you, but you will have to channel harmony powerful enough to restore the other 6 bearers and then together you can free my sister and put an end to Gloom. The fate of Equestria is in your hooves Sunset Shimmer."