As Rainbow Dash, possessed by Zebos, approached the trio, they immediately prepared themselves. Who knew what tricks this monster could pull off?

"How could you... You hurt my parents! I'm so... Peeved at you right now!"

"Ah... I see you've found your parennnnntssss... Yesss... I attacked them just to tick you offffff..."

"Truly, i must say, you are abhorrent!"

"Why... Thank you for the compliment... Failuuuuuuuuuure..."

"If he calls me that again, i swear on my mother i'll...!", Discord thought.

"Release Rainbow Dash right now! Or we will be forced to fight!"

"Oh... Why would iiiiii...?", Zebos said, licking his lips with his freakishly long tongue. "If you wish to free herrrrrr... You'll have to fight... MEEEEEEEEE..."

Before anyone could react, Zebos teleported in front of them, and attempted to slash at them with the sharp, pitch-black claws growing from Rainbow's forehooves. They dodged and teleported quickly, with Fluttershy and Tempest shooting at him, while Discord simply teleported behind him. Discord tried to discombobulate Zebos by clapping his hands on the sides of his head, but Zebos turned around, punching Discord in the face. Discord threw a punch at Zebos' cheek as a counterattack, briefly stunning him, but before Discord could try another attack, Zebos teleported away.

Zebos lashed his tongue around, before shooting a beam of blood from it aimed at Fluttershy and Tempest. Fluttershy dodged by flying around, catching Zebos' attention, while Tempest doged, and kept shooting and blasting at him. When Zebos was going to aim it at Tempest, Discord jumped on top of the tongue, and tied it into a knot. Causing Zebos to distract himself trying to undo it. This gave Discord time to punch Zebos in the face, followed by him kneeing his chin, and slapping him with his tail.

Zebos managed to untie the knot, and tried to lash his tongue like a whip, but Discord got his own whip out, and the two started clashing their whips together. Meanwhile Fluttershy and Tempest kept shooting at him, when suddenly, a gate on the walls of the arena opened, and from it came several demons they faced before, such as Shadow Ponies, Horrors, Shadow Gryphons, Magmoids, and some Hell Dukes.

"We've got company!", Tempest yelled out. Fluttershy and her were forced to shift their attention from Zebos to the lesser demons. Meanwhile, Discord kept clashing his whip with the tongue.

"Give up... Failuuuuuure... You will never defeat-"

"Oh now that does it!", Discord said teleporting around Zebos' neck, and constricting it like a python. Zebos tried to teleport as he choked, but Discord was teleported along with him.

Meeanwhile, Fluttershy and Tempest kept shooting and blasting the demons, destroying many of them in the process, Tempest even using the harpoon for some attacks. Fluttershy even had to resort to kicking her opponents while reloading her crossbow.

Back to Discord, he was still choking out Zebos, but it seems he had enough of the Draconequus' tricks, as he used his tongue to stab Discord, causing him to release Zebos' neck, and then he was thrown to the wall.

"No more gamesssssss...", Zebos said, before stabbing Discord in the chest with his tongue.

"I will enjoy sucking on your vitality... I've heard Draconequus vitality is quite... deliciousssssss..."

"Is it though?"

"What...?"

"I mean, think about it, why would my species' vitality even taste good? We're magical creatures that are a combination of several animals, living, extinct, doesn't matter really. So why, oh why, would we ever taste good?"

"What are you trying to say heeeeeere...?"

"Simple! What i'm trying to say is... SUMODOWA!"

Before Zebos could react, Discord stretched his arms, summoned some cymbals, and smashed them on Zebos' head, stunning him, and causing him to release him. Discord then took this opportunity to continue wailing on Zebos with his whip and his physical attacks, before he teleported away.

Zebos then took note of the situation. Fluttershy and Tempest had defeated his minions, and he was getting beaten to a pulp by Discord. It was time to bust out his secret trick...

"Extinguishhhhh...!"

At that command, the torches illuminating the arena extinguished, leaving all four of them in the dark.

"I don't need my eyes to see you threeeee..."

"Oh yeah? Then prove it-", before Discord could finish, he heard Zebos teleport right in front of him. He quickly dodged away, before the torches flashed to reveal Zebos stabbing the area where he was before with his tongue.

"Don't make a sound!", Tempest yelled out, before Zebos teleported behind her, and once again, tried to stab her with his tongue, but she dodged in the nick of time.

"I told youuuuu... I don't need to see you to know where you aaaaare..."

Then, Discord had an idea.

"Hey, bats! I'm over heeeere~!"

Zebos teleported behind Discord, and stabbed him right in the chest! But this was part of his plan, for the torches flashed again, and instead of Discord...

Zebos had stabbed a giant pole made out of glue!

"Huh...?!"

"Looks like you have found yourself in quite the sticky situation... Haven't you?", Discord said lighting a match.

"But... But hoooow...?!"

"Let's just say i'm a great ventriloquist! NOW!"

Zebos couldn't even react before Fluttershy punched him square in the jaw, and Tempest then blasted him in the back. Discord then leapt, and karate chopped the tongue, cutting it in half. Zebos screamed as he was expelled from Rainbow Dash's body, and the torches re-lit the room.

Zebos' true form looked like a giant horned bat, with a wisp like body, sideways slits for pupils, and massive dark wings, and a collar with a pentagram symbol.

"Well, well, well, looks like we've caught ourselves a strange little bat!"

"All the bats i've met were quite lovely... But you... You are a nd! You harmed my parents, possessed my friend... I'm sorry to say this, but you deserve no sympathy!"

"I'm not even going to waste my breath talking about how you're terrible."

"You foooools...! Look what've you donnnnnnnne...!"

Zebos pointed at Rainbow Dash. Aside from the fact that like Applejack and Rarity, she had features of her possessed forms, she was bleeding from her mouth.

"HAHAHAAAA... When you cut off my tonnnngue... You cut off her's toooo...! Now she'll bleed out and-"

Discord then snapped his fingers, and the blood immediately returned to Rainbow's mouth, and her tongue grew back.

"Oh..."

Discord approached Zebos, holding up his Lunar Rod. Zebos tried to fly away, but Fluttershy shot him with her crossbow, causing one of his wings to be nailed the wall.

"This one's for Mom!", she said, before shooting another bolt on Zebos' other wing.

"That one's for Dad!", and then she grabbed her Solar Rod and pointed it at him.

"And this one's for Dash!"

Both the rods shot out beams at Zebos, who started desintegrating. Once he did, all that remained was a small glowing orb with a cutie mark resembling a danger sign. The world around them flashed white, and when they opened their eyes, they were in the head office of the Wonderbolts HQ, which was trashed.

Fluttershy sighed, exhausted. "I think im gonna need some rest..."

"Oh, that's perfectly fair. We've been through a lot today..."

"Let us return to your house. And don't forget Rainbow Dash."

At Discord's house, Fluttershy, Applejack, and Rarity all looked over Rainbow Dash, waiting for her to wake up. Meanwhile, Discord and Tempest were entertaining the now reunited Cutie Mark Crusaders.

"... And that's how i, Fluttershy, and Tempest, beat that bat, and saved Rainbow Dash from his control!"

"Wooow!", the children said.

"Thanks for saving Rainbow Dash...", Scootaloo said. "Rainbow Dash is still number 1 in my book, but now you might be number 3!"

"And why not number 2?"

"Because my aunts are both number 2."

"Oh, fair enough, i suppose..."

"Nnng..."

"Rainbow Dash?", Fluttershy asked.

"AAAAAH! YOU STAY AWAY FROM THEM YOU... Fluttershy?"

"Well would'ya look at that!", Applejack cheered.

"Glad to have you back, Darling!"

"Girls? What happened? One moment i was screaming at that big blue goat and now i'm... Wherever this is?"

"You're in my house."

"Oh, great what's he doing here."

"Hey i literally saved your oh-so-precious life, so be a bit nicer, will you?"

"He's telling the truth, Rainbow."

"*Sigh*, fine, but whatever. Wait, where's Scoots?

"I'm here!", Scootaloo said, waving.

"Oh, thank goodness you're ok!", Rainbow said, getting out of bed to see her. "Sorry for what i did, Squirt. It wasn't what i wanted to do!"

"I know... So are you a Bat-Pony now?"

"I don't think Bat-Ponies have claws on their hooves..."

"Well, who's next on the list. We've saved Rarity, Applejack and now Rainbow. Who would be next?"

"I believe that the cheery pink one is next." Discord said, pulling out a list.

Meanwhile, at Grogar's castle...

"WHAT?! NO!"

Grogar did not take kindly to Zebos' defeat. He was sitting upon his throne again, when he felt his loss.

"No matter... I still have Ramias. And besides, if they defeat him, i still have my elite guard... And they will surely be enough to defeat them... In fact...

"I believe one of them needs new body..."

He exited his throne room, his shadowy cloak dragging on behind him.

Come... I have a body for you.

As the ponies in the dungeon sat in their cages, the doors to the room opened, and Grogar entered the room accompanied by a large shadowy mass of fog.

"What is that?", Twilight asked in confusion.

"T-twilight...? I'm scared!", Spike said in his cage.

Then, two yellow eyes appeared from the fog, with red trails emanating from them. Celestia immediately recognized the eyes.

"No... NO!", she said in horror. "Not you!"

From the fog, a massive, draconic head with six horns and small spikes on his chin appeared.

"Hello, Celestia."

"Who is that?!", Sunset Shimmer asked.

"Sister, is that...?"

"Mortiferus... But... But..."

"Mortiferus?! As in, the legendary dragon tyrant of old?!", Twilight said in confusion.

"Oh, i see i haven't been completely forgotten. Good, as i shouldn't be.", he said, approaching Celestia and Luna's cell.

"But... But how?! Your cell was supposed to be a secret!"

"I left no stone unturned..."

"Now, pony... I would love to kill you as revenge, but i believe someone else wants to do that more than me., he said, chuckling. He then turned to Spike, who was scared for his life of the dragon tyrant.

"And who are you...?"

"Stay away from him! He's just a child!", Celestia said.

"Hmm. He'll do."

Before Celestia could ask what that meant, he enveloped Spike in shadows, and entered his body, possessing him. Spike's body started to grow, similarly to how it did when his dragon greed got the better of him. He grew two wings, and a long, snake like neck. Four additional horns grew on the sides of his head, and his irises turned yellow.

"Hmm... Yes... He is perfect..., Mortiferus said, feeling his new body.

"WHAT DID YOU DO TO SPIKE?!", Twilight yelled out in horror and anger.

"Oh, so that's my vessel's name? How pathetic..."

"I SWEAR... WHEN I GET MY HOOVES ON YOU I'LL-!"

"ENOUGH! Let us go, Mortiferus. I still need to contact him so he can be here when they arrive..."

"Yes, my lord. I cannot wait to incinerate them...", Mortiferus said, as they exited the dungeon.

Twilight started crying in anger, and despair...

"Fluttershy... P-please come as fast as you can..."

"I sense she has already defeated three of the Archdemons.", Celestia said. "She will come soon. I can feel it..."

Author's Note

Mortiferus is based partially on Smaug from the LoTR series, so i imagine he has a similar voice to him.

Demon Profile:

Zebos
Threat Level: Dangerous
Class: Archdemon
One of the founders of Grogar's cult, Zebos was once a bat-pony named Danger Wing. After his rebirth as an Archdemon, he became a large bat monster, with the ability to suck on the vitality of his prey.