April 1st, 71 BNM
Late Afternoon
Mid-Western Equestria, Mountain Range
Tartarus prison fortress

As cloud banks rolled in, the lights of the exchanged spells, enchanted or flaming boulders being hurled between the fortress and the advancing army began to illuminate the mountain valley.
But the gorge that lay between the walls of Tartarus and the mountain slopes remained to be bridged.

“Get that locked in place!”
Bellowing across the ramparts, Slickhooves ducked as a random fire boulder smashed the wall a dozen metres from him, too low to have hit him, but sending shockwaves through the stone and forcefield.
Ahead, earth ponies cranked the pulleys and gears, the massive wrought iron gates of Tartarus sealing shut, and the large metal lined draw bridge pulling up on the chains they rotated.
Down below, peering over the ramparts, Slickhooves retreated as a few stray arrows shot up at him. A few brave archers and spellcaster ponies had managed to venture right to the edge of the crevice before the walls, inside the magic fields of Tartarus.
Further down on the ground, teams of Unicorns, protected by other soldier ponies, used their combined magic to keep ‘doorways’ open at the base of the shield, unable to break it and instead settling for what was the equivalent of lifting up the bottom of a curtain to get through. The respite was that the holes themselves were too small to let anything bigger than two at a time through, a narrow line to be shot at.
But the garrison had lost many archers and spellcasters already, and more were getting through the small holes than were being killed.
They had no choice, a total lockdown of Tartarus.
Spinning to the nearest guard corporal, Slickhooves’s wings flared as he began to dash towards the nearest stairwell tunnel:
“Where the hell are the reinforcements we were promised!?”
“They’re almost here, half an hour!”
Whipping to the corporal pony, Slickhooves darkly muttered as a fiery boulder shattered against the shield, fractures forming as the utter torture of the bombardment began to take its toll.
“They’ll owe us a lifetime for making us endure that much more of this…”
Nearby, a volley of arrows from the archers that had penetrated the shield struck an Earth Pony in the face, as a group of guards he was with cranked levers on one of many vats that had been magically heated by Unicorns to extreme temperatures.
As the massive vats were tipped, a few spells fired from guards set the liquid ablaze.

At the base of the wall, just short of the nearly endless depths of the defensive crevice, the archers and spellcaster ponies stopped short as the multiple vats tipped over, their oil contents set ablaze.
In panic, retreating back before it could land, they scurried out of the narrow ‘doors’ the other Unicorns had kept open in the barrier, as the burning oil loads carpeted the terrain between the crevice and the shield’s edge, and even beginning to seep out.
As a few Unicorns and archers dashed through the barrier, they realised what they already suspected. The Tartarus shield was one way, able to be passed through only from the inside.
As the oil slick began to spread like molten lava down the slopes, storages of oil feeding into the dumping tubes from on high, the forward portions of the Nationalist army were forced to retreat. Dozens were caught before they could flee the oil shower, and many were badly scarred if not killed by the agonising siege defence.
Forced away from the walls, all assault on Tartarus yet again fell to the long range bombarding siege engines.

Tartarus’s interior halls

Having snuck into a stairwell before the lockdown was ordered, after an arduous climb, Chack kept his enchanted sword active, his body invisible to the naked eye.
Dashing down cavernous stairwells left, right and centre, he finally found the main atrium and assembly hall.
There, as ponies strained with it, the gates of Tartarus.
Cocking his head at the sight, Chack mused to himself: “Less intimidating from this side… But if they try anything, it’ll be here.”
Scrambling down the steps, he found a small alcove where he could wait patiently. The gates, and entry to capturing the fortress, would be a key target. If any of the beings entered the fray directly, they’d be here at some point.
As a hundred guards readied many blockades and locks on the gates, Chack peered through the torchlit halls, and the cavernous drop down below at a stairwell.
He heard a certain 3 headed dog snarl from down below, as he recoiled from the banister with a wide eyed expression.
Ground floor was probably the best place to be anyway.

Opposite mountain top, Nationalist command point

Overseeing the battle, it was the messages that arrived next that turned the tides.
Nationalist scouts flew in, the Pegasi having sighted an army advancing by land and air from the west, flying Royalist colours, and coming fast.
The inevitable reinforcements of the Royalists.
But their own reinforcements were inbound as well from the East and North, one a conventional army, the other heavier and less conventional.
But given her command, Teal Quirt made the judgement, the pale Unicorn ordering the commanders:
“Signal the army, allocate two in every three siege engines to be ready to change direction. Our army incoming from the east will assist against the Royalist reinforcements, the other from the North we will allocate depending on the outcome.”
“The fortress is locked down, if we reallocate the engines the barrier will regain strength.”
“And if we finish it, by the time it is down the Royalist army will catch us waiting to surge into it from the flanks. Deal with the more immediate problem, our northern forces will deal with the fortress.”
As her orders went out, Teal wondered what was taking Odi-Viscer and the Stone Giants he was leading so long, or the army from the east Golmov was escorting. They were due in half an hour, they should have come into sight by now.
Within minutes, the number of siege engine locked and aimed to fire on Tartarus’s shield and the gates had begun dropping to a third, and sure enough, the barriers stopped weakening and settled into a steady state. A necessary delay of their siege rate to avoid being caught off guard.
Those siege engines not firing stood ready to rotate and aim at the expected retaliatory army from the west.
Minutes passed, and yet the army did not come.
From the north, more tremors came.
And before long, Teal and the commanders, from their mountain top view, saw a few rocky shapes moving in the distant valleys out of sight, the hulking forms of the reinforcements like the sight of shark fins on sea from behind the mountains they were traversing through, swifter moving by following the valleys, rather than having to climb over the mountains one by one.
To those in the valley itself, these titans were still out of sight, though the faint tremors were felt, lost amid the rumbles of the thousands already in battle.

Western mountain ridge

Peering over the mountain top, the Royalist scouts saw the army having pulled back from the gates, and the majority of their forces bracing to counter their assault from the west.
And from the north, an unbelievable sight were it not seen by many eyes.
A dozen Stone Giants, marching through the valleys to save time. A mountain ridge blocked their way to Tartarus for now, until they reached the front gate valley.
But for the Royalists, they had a clear goal, to keep Tartarus under control. If not the fortress, then the mountain top.
A plan was made, using the maze like nature of the mountain valleys to their advantage.
Behind the ridge, the large army split in half, and made their move.
One half, 3000 strong, ventured east, circling around Tartarus’s mountainous reaches, to catch the Stone Giants from behind and do, something. Those giants were so big that they could only be meant for the fortress, not a mere army.
The other, another 3000, ventured over the mountain, setting up for an initial volley.
Pegasi forces took flight, and set to work.
Those skilled in weather control had aligned in the majority with the royalist side at this point in the war, an advantage that was not to be wasted.

Evening
Mid-Western Equestria, Mountain Range
Tartarus prison fortress
Valley battlefield

Aubelles stood fast, the bronze armor he wore covered in burn marks and a few flecks of blood. Now that the army was preparing for a new form of combat, he had some respite. The fortress lay before them to the right, taunting them with its barriers now able to cope with only a third of their siege engines firing at it.
For good reason, as the first signs came from the West of something big. And while their own reinforcements were coming in fast, what was the opening attack of the Royalists was something that could only be defended against by bunkering down.
Cries rang out in panic, others in preparation, before Aubelles’s voice joined the ranks of voices, his own magically magnified to reinforce the will of the ponies he fought with, and was respected by for experience, not his Alicorn status:
“Hunker down! Dig in lads, they’re trying to storm us apart before they strike!”
Over the mountain ridge, forced low by winds unnatural by normal weather, a thick wall of black storm clouds surged over the ridge a mile ahead, moving in fast, the air turning thick and fogged by what appeared to be torrential rainfall from the massive storm system being driven towards them.
Surging over, the black clouds drew closer, the ground in the valley darkening as their shadows and the rainfall overcame them. Closer and closer they drew, until they reached the ranks of the army.
Aubelles held fast as the torrential rain and hail began to pummel them, as the air darkened with the purposefully low hanging storm clouds rushing overhead. The hordes of soldiers around him held fast, Unicorns and himself, along with the other 2 Alicorns who had been injured slightly in the initial air attacks on tartarus, formed shield magic to protect from the rainfall.
Darkness washed over the battlefield, but on high in the mountains and fortress, the valley looked as if it had been drowned in a sea of black clouds, white light flickering as a few flecks of lightning and thunder burst here and there.
From behind, a few sieges engines opened up volleys into the black storms, knowing this was a tactic to cover an advance on them. Fireballs of magic and normal variety flew through the air, too big to be diminished by the torrential rain and hail, nor the gale force winds battering the army.

Obscured by the clouds, the unseen hundreds of ponies charged, magic or armor protecting them from the hail and rainfall they were covered by. Lighting bursts lit up the clouds as they charged into the abyss that covered the plains, the 5-minute long charge illuminated by the thunderclaps and their electric sources, and the hail of random hurled siege boulders by the army they were charging towards.
Hooffalls were masked by the thunder and downpour, as they charged. A few ponies were struck by lucky boulder landings, but they charged on.
Soon, they saw them, a horde of dark shapes hunkered in the downfall they engineered by Pegasus magic to cover their advance, and their gallop turned to an all out sprint, their war cries nearly lost in the thunderclaps and downpours.
They saw them too, and the Nationalist lines turned to stand, pikes forming, magic horns beginning to glow, weapons prepared.
But the Royalists had closed the gap enough in the chaos that their defence was not impenetrable.
As the first wave hit, thunder roared overhead as armor and weapons clashed, mud and rain flying as the Royalist charge impacted the Nationalist horde and began to push.
Overhead, sensing their storm was no longer needed, the Pegasi that had been flying around to form it eased up, flying down like vultures in the rain soaked darkness to join the fray.
The dark clouds hung over the battlefield, but they began to slowly bleed off as the two armies reappeared from their masking presence.
Thousands of Royalist ponies fought close quarters against the Nationalists, having punctured into their hordes to throw them off guard, rendering their siege engines and long range weapons useless now.

On the ground, Aubelles fired his bronze magic, a wave sending a trio of Royalist soldiers flying backwards in scorching heaps, as the carnage unfolded around him. Swords and spears flew with magic from both sides, blood flying, curses and screams over the chaos filling his ears. Terror that would grip civilians gave him drive.
Here was where he thrived, but he would have preferred not being caught by a Royalist weather tactic to get here.
Charging through the rain soaked muddy ground, Aubelles summoned weapons from fallen Nationalist and Royalist soldiers alike, his magic flinging them to and fro at his command, while his magic fired at every Nationalist he could find.
“Fight, through rain and fog, day and night, fight for the cause!”
Aubelles roared his declaration to the rest of his kin fighting, as he found a group of brave Royalist Unicorns working as a team to protect themselves and take out many Nationalist soldiers at a rate he nearly was their own.
His own magic flaring, Aubelles surged forwards, hurling a Royalist soldier aside with a swipe as he engaged the Unicorn team, bronze magic meeting their collective purple as it joined one of many illuminations amidst the carnage unfolding in the valley.

Tartarus valley, opposite mountains

Seeing the carnage unfolding below, the commanders had rushed to ready the flag and horn war messaging systems they had as soon as the clouds fully rolled away for them to be able to signal the armies.
In the distance, Teal saw their first reinforcements coming, as the Stone Giants were now only 3 miles away. Turning to the commanders, she decided now was the time to enter the fray herself.
“Assume command, stick to the plan. I expect that these aren’t the only reinforcements the Royalists have for us!”
At her word, and as they rushed to continue the signal readying, Teal teleported away in a green flash, knowing who she had to go to first.

North east of Tartarus, valley passages

Marching slowly ahead of the between 100 and 200-metre-tall giants behind him, 12 of them, along with 400 soldiers from the various Nationalist forces to escort them, Odi-Viscer strode forwards in his bald Earth Pony form. The young stallion and being of Wrath gave no order to halt as a green flash came before him, and Teal Quirt emerged.
Walking beside Odi-Viscer, the Unicorn quickly summarised the battle situation, but she was not at all panicked. The soldiers marched further back, as the earth trembled with the 12 stone giants even further behind.
“How quickly can you get to the gates?”
“20 minutes.”
“Good, we can have this-.”
BBRRRMMMMM!
A colossal bellow came from one of the rear Stone Giants, as all in that valley, and even a few ears in the battle unfolding before Tartarus 3 miles away, heard it. At the rear, a 150 metre tall Mantis shaped Stone Giant had noticed a moving army, and sure enough, eyes in the same valley saw the Pegasi that accompanied them too.
“We’ve been flanked!”
A cry rose from their ranks of 400 soldiers escorting them, before Odi-Viscer turned to nod to one of the Pegasi with them, who flew up to get a bearing on the army they could understand.
“If the giant is alarmed, this might become a problem…” Teal began, to which Odi-Viscer spat angrily:
“Forget the giants, they can handle any army.”
“But Tartarus remains sealed. We can’t let it remain that way, and the giants won’t let us easily capture it without utterly obliterating it. Siral was clear, he wants its insides mostly intact. No Canterlot situations this time if it can be helped.”
Grumbling, Odi turned to hear the Pegasus from overhead, as a pair of the Giants had actually flat out turned to confront whatever army was coming:
“No more than a few thousand, same size as the one before the gates!”
“If we take Tartarus, it makes things easier. Now begins our part Odi…” Teal began, to which the Earth Pony actually smiled widely at the prospect of this. She spoke to the 400 ponies waiting behind them:
“Keep ahead of the incoming army, let the giants defend themselves, but expect to be slowed by them fighting. Stay with them, use them as mobile castles if you can. Tartarus will be open by the time you get there!”
A few cheers went up, as Teal turned to Odi-Viscer with a nod. The pair of them vanished in a green and red flash, while the massive stone giants continued at a slower rate, some of the giants at the rear strafing sideways like a crab as an army of ponies, flying, earth and magic, came rushing over a small ridge, a hail of magic peppering their bodies as the Unicorns led the charge.
The line of giants pressed on, only the rear 4 turning to mildly confront this assault of random pony attackers in the hundreds, like fleas biting a horse.

Tartarus northern mountain ridge

Quickly flying up the shallow slopes of the mountain’s top, Celestia and Luna followed a few Unicorns learned in using the weapon they were heading for. But in the distance, they could see the line of Stone Giants pressing through the distant valley. Some like a Bear, others like Apes, more like a Tortoise, and one like a Rhino, all heavily built.
The surging army of 3000 fighting those at the rear of the line were horrendously outmatched, their magic and weapons barely scratching the creatures as 2 of them completely turned to advance on the army, forcing them to pull back.
Looking on, Luna shook her head with dismay and fear, before she turned to Celestia beside her in the flight, telling her with staunch certainty:
“Go on ahead, I must help them, or they’ll be killed!”
“Luna, no, we have to get-.”
“I won’t be long, but they must see the best way to take out a mountain for themselves!”
With a flash of blue, Luna soared away, down towards the armies being pushed back by 2 of the Stone Giants now. In fear, Celestia continued on, Tartarus’s mountain top looming ahead.
Coming inside the bubble of Tartarus’s shields, let in by some guards who could form holes on the ground, the Royal sister came to land at the alter like structure.
“Your majesty, it will take time to get it ready, allow us.”
Nodding at this, Celestia couldn’t help but be drawn to the southern edge of the alter, to a point that overlooked the valley below.
Wandering there, seeing through the barrier and down the slopes before the steep cliff face of Tartarus, she glimpsed the unfolding carnage below, and could not make sense of such attrition below.
How many hundreds were already dead was what she wondered in her mind.

Tartarus, north-eastern rim

Bellowing groans louder than a thunderclap filled the air as the 2 Stone Giants pressed forwards, Pegasi scattering as they flew about like gnats, trying to find a weak spot in the giants. Below, Earth Ponies had long given up on fighting, and had begun to fall back, while the Unicorns fired randomly at the creatures’ heads.
The Bear shaped stone giant reared up as it charged, and its two forelegs slammed onto the hillside with force to send out a ripple in the ground, a few Earth ponies and Unicorns caught too close actually having their ankles shattered from the impact, and a few very unlucky ones caught underfoot as the other, an Ape shaped Stone Giant, rampaged nearby with forelegs stamping down as if crushing ants beneath its foot.
Flying down, Luna bellowed to the soldiers as she charged her horn, straining at the raw energy she was using:
“Stand together, focus your power on one spot!”
A fierce blue beam fired from Luna’s horn, as it burrowed into the shoulder of the Bear Shaped giant, earning an ear splitting bellow from the 150-metre-tall creature, as it visibly staggered from the penetrating blow to its body.
Sensing the powerful attacker, the Ape shaped giant began to charge at Luna, but as her example showed, its face was bombarded with magic from every Unicorn in range, a few hits focusing on the glinting silver eyes finally making it shriek loud enough to rock the air itself, recoiling as it stopped it charge.
Looking down, Luna saw the soldiers below her get the memo, as cries rang out to aim together on their commander’s mark. Spells, arrows and crossbow bolts enchanted with potions or magic all now flew at specific targets all at once, and now every volley actually did noticeable damage to the Giants.
But a few roars from some other giants ahead alerted Luna to the fact that this strategy had made their half of the army a bigger target. 3 more of the Stone giants had begun to fully advance, leaving seven of them to march ahead with their escort troops having slowed their advance to climb aboard, the seven near 200-metre-tall beasts now walking fortresses themselves.
“Slow them down, go for the leg joints!”
Hearing this, Luna turned to see the ponies working together on the mountain slopes, their fire hitting the knees of the 2 nearest giants with enough force to begin chipping through the massive joints.
But the nearest of the 3 charging Stone Giants had chosen Luna as its target, and she cautiously flew upwards out of its reach. A silver light glinted in the Lizard shaped giant’s eyes, as it stared up at her.
Then, a fierce burning light shot from its eyes, twin beams joining to close in on her. She quickly teleported, reappearing as she saw the white beams pulverise the mountain slope further behind her, sending rocks shattering and rolling down the slopes. Blinking, she had an idea amidst her fearful reaction.
Flying about, she saw the charging Giant coming after her, eyes glinting for another attack from below her. Firing a few blue magic bolts, she couldn’t help but snort as she saw her soldiers follow her example and fracture the leg of the first Stone Giant, slowing it immeasurably, while they turned to focus on the nearest other one.
Below, the Lizard shaped creature’s eyes lit up, as the scorching beams lit up the evening skies to come at her.
From afar, the blue light as she used her magic to deflect the attack flashed, and roared like a lightning bolt. The destructive magic bolt was reflected back, hitting one of the Stone Giants that had been coming up from behind, hitting it in the neck to fully decapitate it.
Roars of victory amidst an ongoing battle filled the air as Luna flew around, trying to goad the Giant into attacking her again. And sure enough, the simple minded mountain creature fired again.
Her first one hit kill was a lucky shot, her reflections were not as accurate afterwards, but enough.
But in the distance, as she reflected another shot to blast a good chunk of another Giant’s boulder shoulder off, as 1 more turned from the fortress advance to aid against this army that flanked them, she saw an advancing army a mile away.
Nationalist reinforcements from the East, normal troops this time.
Sparing a glance at the mountain top, Luna prayed that the weapon would be ready before too long passed.
But from below, a silver light filled her vision, as Luna had become distracted.
Right before she could even begin to think, before it incinerated her, Celestia’s yellow magic flashed and deflected the blast far away, the blast so powerful that it actually hit within a few hundred metres of the 6 Stone Giants still advancing on the fortress over 2 miles away, the blast noise audibly delayed by the distance.
Whirling around, Luna saw her sister beside her, Celestia speaking sternly, but with well-meant warning:
“If only your focus was as good as your quick thinking against these beasts!”
Down below, the army of 3000 surged around, weaving as the presence of two Alicorns with them acted as battle means and motivation. Even with a seventh turning to head towards them, they had downed one, and wounded two others.
Still, as Celestia had joined the fray, she had too seen the reinforcements for the Nationalists that had arrived.

Tartarus Valley, eastern edges

Amidst the flanks of Nationalists and Royalists engaged in the battle, the sight of thousands more marching fast towards the valley was a blessing and a curse respectively.
But the sighting of no less than Six Stone giants advancing through another canyon into the valley basin nearly paused the battle entirely.
The Nationalist armies began to retreat back, towards the advancing reinforcements, with the Royalists having only the choice to chase, take out as many as they could before they regrouped.
Pegasi started up the thunderstorm cover yet again, but the battle was so close quarters it was not as effective as the initial attack.

High in the skies, overseeing the advancing army to aid the attack, Golmov new the other two would be on their tasks by now, to infiltrate Tartarus from the inside, however they saw to do so.
But as he turned to see what he could do next, he saw something with his magic enhanced and draconian vision. The Black and Gold dragon recognised that Yellow and Blue magic reflecting the eye beams of the Stone Giants anywhere.
He would never forget the magic of the Alicorns that humiliated him by actually managing to intimidate him into surrendering the Crystal Heart from his hoard.
With a snarl, he turned, and flew directly towards the battle taking place north of Tartarus, of half the Royalists versus 6 stone giants, with 2 Alicorns in the mix.
“Finally, revenge…”
His body glowed yellow as he beat his wings hard, not quite ready to reveal his true form to the two princesses yet.

Tartarus, fortress walls

Ignoring the oil slicked slopes, the two approached the now desolate grounds that lay before the walls of Tartarus.
Approaching the barrier, ignoring the distant sounds of carnage in the valley only a half mile away, and both of them rendered invisible by their magic to the eyes of the archers who had remained outside the lockdown, the two examined it.
Feeling it with her hoof, Teal Quirt looked at the crevice that lay immediately after it, remarking to him:
“Remember, intact.”
The Earth Pony rolled his eyes as Teal set to work, her green magic forming a shield as she also fired a beam at the Tartarus barrier, turning them both visible as it did so.
Surging forwards, his form altering, Odi-Viscer’s apelike, stone skinned forearms ripped their claws into the barrier, straining as he literally began to slowly tear a hole through it, fighting the barrier’s constant efforts to seal the hole.
As the cries from on high came to fire on them, Odi-Viscer couldn’t help but notice a familiar shape far overhead in the sky flying north, his arms still pulling open their entry through the barrier.
“Where’s Golmov going?”
Looking up as she continued her spellcasting, Teal remarked offhandedly: “Wherever he is needed I presume. Its good he actually has an interest in battles like this besides the looting afterwards.”
“No, but he may like the vaults in Tartarus once the day is done.” Odi suggested, not at all gritting his teeth as he continued to pull apart the hole in the barrier.
“He was, and still is, a dragon by birth, some things don’t change.” Teal remarked, as a stray arrow was incinerated on her shield during her remark.
Arrows and spells continued to rain upon them, but it was not long before Odi-Viscer had pulled apart a hole big enough for him and Teal to step through. Prising it open as far as he could muster, he let Teal leap through, her form changing mid jump to her centaur/scorpion and ape torso form, her claws gripping the crevice walls as she cleared the gap between the shield/crevice edge and the wall.
Leaping through himself, Odi-Viscer audibly yelped as the shield snapping back into place sliced a tiny sliver off the ball of his stone skinned rear foot. Gripping the walls, both of them slowly climbing down to get out of arrow and spell range, Odi looked at his heel, noting the tiny sliver was glowing red hot.
“Probably get cut in half if you’d been slower.” Teal remarked, as she too climbed down into the depths of the crevice.
Down here, the crevice that led into the lowest depths of Tartarus, there were skeletons of ponies who had fallen to their deaths, long in the past, some as recent as the battle today. But they ventured further down, to where even the brightest sunlight wouldn’t reach.
Their green and red lights illuminated the way down the whole time, as they sought the most ancient of passages that would let them enter Tartarus from its lowest depths.
With the battle unfolding in the north, and south of Tartarus, a skirmish was set to begin on the inside between fewer individuals.
But they were also being hunted themselves by Chack, who knew the gates were their primary target.

Author's Notes:

Opening up the battlefield to a three-way theatre, though stone giants do not a victory guarantee.
Luna, and then Celestia, lead by example while the weapon is readied, though in the process of them helping they’ve attracted the vengeful eyes of a certain greedy individual that killed their father.
Meanwhile Odi and Teal take the planned initiative to open Tartarus from the inside, though Chack anticipated something roughly along these lines as it was.
Speaking of which, later in this battle will see Aubelles and Chack reunited, however that goes.