---3rd Person POV---
Having heard about the destruction of nearly all Dark Guilds on Ishgar, Tartaros mobilized Plutogrim and fled from where they usually resided. The Guild's intelligence network was able to find out who was destroying the Dark Guilds, Mael of Fairy Tail. Deciding that his Guild needed to pay for the destruction of their subordinates and allies, they opted to attack Magnolia while he was away.
"Why the hell can't we just kill the Council and activate FACE!", Jackal spat in anger, "Running from the enemy like this is degrading!"
"You can blame whomever leaked our plans to the Magic Council. Our double agent Crawford was apprehended in the middle of the night, and all Council Members are under heavy protection now.", Mard Geer told him, "Tracking them down and killing them would take too long now. Mael had already destroyed over ninety percent of the Dark Guilds in a few hours. Based on what we learned from the Kingdom, Grimoire Heart lasted less than five minutes against him and they were of similar strength to us."
"You mean Hades was, the others were of little consequence.", Kyôka clarified.
Agreeing to disagree with that, Mard Geer knew his peers weren't taking this threat seriously. It took him over an hour to convince them to mobilize, all because they thought the mage wasn't that powerful. Unlike the others, he could feel something about Mael that made him shiver to his core. The way he wiped out Guilds in a matter of seconds...the power he detect made him want to run away in fear.
"So we are just going to wipe out the city, and flee?", Seilah inquired as the city came into view.
"Correct.", Mard acknowledged, "We will destroy it and continue on to a new location."
"We are fifteen miles out, we should be in range in a few...", Lamy started to say as something flew past Plutogrim on their radar.
Before she could say anything, Plutogrim came to an abrupt halt causing everything to get tossed around. Thrown forwards by the impact, all of them were brought to the floor as the entire structure started to buckle. After a few moments of violent shaking, everything came to a standstill as the momentum died off. Asking if everyone was okay, the Demons picked themselves up to figure out what they hit. Flipping on the monitors to see what happened, they saw Mael looking straight at them holding Plutogrim back with a single hand.
"You certainly have a pair on you to think attacking my home was a wise choice.", Mael remarked as Plutogrim started howling in pain as it started burning uncontrollably, "You are the only Dark Guild remaining, why don't you come out here and face your death with some dignity."
"I got this!", Jackal said as he rushed out of the control room with Ezel, "Time to beat the shit out of this arrogant fucker!!"
"We should focus on a group attack not...", Keyes tried to suggest but they were already gone.
"No, this will work out for the best. Splitting up into multiple small groups means he will have to divide his attention. If some of us can get into Magnolia we can use some of his comrades as hostages.", Mard told them, "For now, let Plutogrim preoccupy him while we slip away."
Agreeing with his decision, the remaining Demons split up and made their way to one of the many exits. Down in Magnolia, the populace were being rush to the Fairy Tail Guild Hall by the Knights stationed in the city along with the Fairy Guild Members. Doing their best to ensure no one was harmed during the rush to the shelter, Elfman and Midnight were overwhelmed by the sheer number of people in the streets.
"Everyone stay calm and hurry to the Fairy Tail Guild Hall", Elfman ordered helping the elderly and children stay on their feet.
"No pushing!", Midnight shouted out at a few grown men trying to bulldoze their way through the crowd, "I said no pushing!!"
Grabbing them the brothers Walley and Richard pulled them out of the crowd to prevent anyone from being injured. Telling them they would face serious charges if they didn't follow the orders being given, they assured them that no one was going to be left behind. Getting them back in line, the Knights and some Fairy Tail Members started going door to door making sure no one was in need of assistance.
While the Knights and those Fairy Tail Mages were helping with the crowds, the stronger members were already enroute to fight the attackers. Having watched Mael stop the flying monster, they wanted to assist as it was well known that Tartaros had many guild members. Knowing that Mael would likely focus on the core members, they needed to hold back the normal members till help could arrive.
"Alright, time for some real S-Rank fighting!", Laxus said as the core members started coming out of the flying monster, "Let's do this!"
"Yeah!", the Thunder Legion agreed.
"Don't get to carried away, these people are a lot smarter than a normal monster.", Gildarts warned.
"Right, don't let the rush of battle cloud your judgement and senses. These people are your family, keep your eyes and ears open.", Kratos warned them.
As they drew closer to the grunts charging at the city, Mael was already moving to intercept the core members. Knowing that Keyes and Tempester were the most dangerous at the moment, due to the high level of Anti-Ethernano they contained, Mael bisected Plutogrim before giving chase. Hearing Plutogrim's death throes as their comrade fell to the ground as it burned, the Zeref's Demons became increasingly angry at Mael.
Flying after them at high speed, Franmalth and Torafuzar hung back to fight Mael. Seeing him as a genuine threat now, they were willing to sacrifice themselves by their allies time to reach Magnolia. While Mael was momentarily bothered by the two men, the rest of their group reached the ground and hurried towards the city. Running straight into the approaching group of Fairy Tail Mages, both groups stopped to size each other up.
Sensing that they were all relatively powerful mages, they carefully thought about how to proceed. Hearing Franmalth and Torafuzar die only moments after engaging Mael, Jackal decided to make the first move.
"It's now or never!", Jackal said rushing forward towards the mages, "If I am going to die, I am taking as many of you with me as I can!!"
Creating cover for his comrade, Tempester blasted the mages with several powerful bursts of wind and fire. Keeping up the pressure on them, suddenly two blades shot through his attacks and pierced his chest. Jumping through the fire, Kratos slammed into him as he yanked his blades back. Watching the blades start to spin rapidly, Tempester quickly turned himself into wind narrowly avoiding being decapitated.
While Tempester kept Kratos preoccupied, the other Demons attacked the Fairy Tail Mages. Hearing Mael blasting their ranks to pieces as he shot towards them, Keyes decided to lay it all on the line. Letting his anti-magic particles run rampant, the mages didn't recognize the danger they were charging into. Seizing this opportunity, Tempester created gale force winds to carry the cloud towards the Mages and Magnolia.
Before the cloud could move very far, some sort of barrier stopped it. Running smack into the barrier, Erza looked around trying to figure out what was going on. Seeing the light reflect off the barrier, she realized it encompassed the entire city limits.
"What the hell!", Jackal yelped as he smashed into the barrier, "Why won't this thing break!!"
"My particles should be able to destroy their magic barrier.", Keyes said in confusion, "Why isn't it working?"
Suddenly the sky started darken as the wind started to howl. All over Ishgar the Sun disappeared from the sky as darkness fell over the land. Violent storms broke out all over the peninsula as tornados and lightning destroyed the countryside. Safe under the barrier, the Fairy Tail Mages watched the Tartaros Grunts rush towards the barrier. At first they thought they were trying to break it, but then they saw the horrified looks on their faces.
"What is going on out there?", Laxus asked.
Flying through the barrier, Kratos quickly stopped his slide as he kept an eyes on the outside. Telling everyone to stay inside the barrier Kratos warned that stepping outside would get them killed almost instantly. Questioning what he meant, the grunts pounding on the barrier stopped and quickly began tearing each other apart like rabid animals.
"Where is Mael?", Gildarts questioned.
"Who do you think is causing this?", Kratos replied, "He put this barrier up to protect you all from what he is doing."
"Which is?", Irene inquired.
"Show them what a True Demon looks like.", Kratos answered using Mael's words to him.
Back at the Magic Council Building, everyone was holding on for their lives as wind tried to tear them from the building. Barely able to hear one another of the howl of the wind, Goldmine and Yajima were asking Makarov what was going on. They had never seen such devastating weather in their entire lives, let alone a mage capable of causing it.
Holding Dalton down so he didn't get torn up by the shattered glass, the Defense Minister looked at Arcadios with a serious expression.
"Do you still think it wise to antagonize the man any further? Clearly he has been holding back quite a lot!", Dalton shouted so the knight could hear him.
'What sort of monster is he!?', Arcadios thought looking at the screen.
As lightning came down where the battle was happening, Arcadios caught a glimpse of something that made his grip on Dalton tighten more. Seeing a giant man standing nearly 200 feet tall dressed in black armor standing outside Magnolia, something about the man made his very soul quake in fear.
"What is it!?", Dalton asked.
"I am afraid we may have angered something far deadlier than any Mage...", Arcadios remarked.
Outside the barrier, the core members of Tartaros saw their men tearing each other apart. Trying to understand what was happening, they felt the ground shake as if a large creature was approaching them. Sensing that something was coming, Mard let go of his handhold and let the wind carry him away. Watching him disappear from sight, they were confused why he left them behind. A split second later, Kyôka saw a metallic glimmer as a bolt of lightning came down nearby. Letting go as well, she watched all of her comrades explode into millions of pieces as a massive sword slashed them in a matter of seconds.
"Why do you flee from me..?", a booming voice said as a hand reached out from within the darkness, "Are you afraid?"
Seeing Mard already caught in the hand, Kyôka was unable to avoid as the wind literally forced her into the hand. Pulling them both towards the main body, they both started shaking as they saw hallowed, black eyes starting at them from under a horned helmet that looked made from the bones of thousands of dead bodies.
"What are you!?", Mard shouted in terror.
"I am the Demon King Estarossa.", Mael responded as the air reverberated his words, "You are not Demons, you are merely a cheap imitation of one. How dare you suggest that you are anything, but that."
Feeling him start to crush their bodies, the two of them wriggled around trying to break free. Ordering them stop resisting, they suddenly found that their bodies wouldn't listen to them further.
"You imitations are no longer allowed to live on this world.", Mael told them, "Purgatory Flames."
Spontaneous erupting into purple and black flames, the two of the writhed around for a few moments before turning to dust. Watching the site from the ground, the mages were in shock as how effortlessly they died. In just a few hours Mael devastated nearly all of the Dark Guilds, and those who he hadn't were all probably on the run now. Before they could call out to him, Mael vanished from view faster than they though give his size.
Back at the Magic Council Building, all of those who had been watching were equally confused.
"Where did he go!?", Arcadios shouted as he saw him disappear from the screen.
"I am right here.", Mael said staring at him through the shattered wall of windows.
Seeing him in person was even more intense than it was through the screen. Several of the Council Members and Guildmasters fainted just from his presence alone, even Dalton was unconscious at this point.
"Heed my words well, do not test my patience. As I have said, I will see the King tomorrow at 10am.", Mael stated, "It goes without saying if you attempt to harm anyone in our Guild...you won't even see your death coming for you. This warning especially goes towards you...Jose of Phantom Lord."
"...what do you mean..?", he asked turning snow white.
"I know your dealings with the Mage Hunters. If you try to attack Fairy Tail, you will face my wrath.", Mael said as the room started to freeze over, "I will hunt you down to the ends of the world to drag you to the pits of hell."
Feeling a wave of killing intent hit him, he made the mistake of looking into the hallowed eyes of Mael. Starting to laugh like a maniac, Jose had a mental breakdown as the voices of those he led to their deaths started overwhelming his mind. Shouting at Mael to make it stop, Jose started clawing at his ears as he let go of his handhold.
"I will be watching you closely.", Mael said as he vanished from their sight.
Shaking violently as he saw the trail of devastation left in Mael's wake, Arcadios instantly acknowledged he had been a fool. Had Mael wanted too, there wasn't a damn thing anyone could have done to stop him. Knowing that a monster like that had been living in Fiore all this time, Arcadios was relieved the King hadn't sided more with the Church and Mage Hunters. If he had...the country would have been destroyed.