"Come with me, there's something I wish to show you two"
The king of the monsters led the dark knight and the fallen child to an area pass the throne room: the vibrant color of the flowers soon faded to obscurity, leaving only a gray environment within the next room they entered.
Sparda could feel the child beside him tugging on his sleeve. While determined they were to see this through, it did not mean that they walked in without any concern.
"This is it" Asgore spoke, gesturing to the door on his right. "Now before we go any further, I want to know if you two are ready. If not, I understand... I'm not ready either..."
"What do you mean?" Sparda narrowed his eyes, only for Asgore to return that gesture with a mournful smile.
"The reason why my people remain here"
Upon entering the room, the duo were greeted by a strange sight: were they stood was what seemed to be a large hall, pulsating a white light that travels far to the other end.
Asgore stopped walking as he stared at the pulsating room, almost in a catatonic-like state.
"Where are we?" Sparda asked, gently moving the child behind him.
"The barrier" the king replied, not moving from his spot. "It's what keeps my people from walking into the soothing morning or the beautiful evening. Ever since that war, humanity had place this seal in hopes we never roam the earth again."
"Even despite knowing our place's true nature, my people did not give in to despair and continued living within the underground" the king gave a sideways glance to the two behind him, "but that moment of hope was crushed when their prince - my son - died at the hands of humans"
Seven medium-sized containers then erupted from the ground, six of them holding something strange.
"In order to bring back hope to my people, I will do what I must" Asgore slowly turned to face the two, his woeful smile still in place. "it was nice knowing you two... farewell..."
A crimson trident suddenly manifested into the king's hands, who then proceeded to pounce onto the two. But before the trident's aim rang true, a large, thin piece of metal got caught in between the trident's prongs, pushing the king of monsters away as Sparda manifested his own weapon:
A massive sword that can reach the length of his legs to his shoulders. While the sword appeared to be your average blade, what separated it from the rest was the strange skeletal-like design that makes up its crossguard.
"Why are you doing this!?" Sparda asked, only for Asgore to say nothing in response. "Answer me! Have you no shame in killing a child!?"
"A king's duty is to his people, even when it calls to make a difficult choice" Asgore spoke, his will not faltering. "When a monster absorbs a human soul, they become a fearsome beast with terrifying power. I've only captured six so far..."
"Then those containers... they're housing souls..." Sparda muttered aloud, before reinforcing his sword stance. "Why do you need so many of them?"
"With seven souls, I can become godlike and free my people of this prison." Asgore explained, "our future has been taken twice by humanity, I will bring security and peace to monsters by wiping humanity out before they can do so to us"
"I see..." Sparda quickly pushed the human child away from him and the king, before silently uttering something to himself: strange rune-like symbols manifested onto thin air, before suddenly creating a black translucent barrier that separated them and the child. "I'm sorry, Your Majesty, but I can't let that happen"
"And I can't let you stop me, not when our freedom is so close."
A scene flashed vividly in Sparda's mind: a beautiful woman sat next to two boys atop a blanket, lulling them to sleep with a soft melody. She seemed to have noticed that she was not only one awake, and quickly returned the Dark Knight's gaze with her own.
They both said nothing. Instead, the woman only smiled gently at him.
"Not when I have too much to lose..."
He gripped tightly onto his claymore, letting out a cry of valor as he charged for the king under the mountain...
Frisk knocked against the black barrier between them and the battle, hoping to find a weak point somewhere they could exploit. As they looked past the translucent wall, they could the ferocity between the two men as they fought.
They need to find a solution quickly before things get out of hand.
One's swordsmanship is often gauged by their talents, and Sparda was no slouch in it. There's often something quite elegant with the way he fights, his form similarly akin to that of a gentleman. But even so, Asgore kept up a similar pace.
Their resolve unfaltering as they danced with death, neither side yielded to the other.
Until one makes a tiny, yet exploitable, mistake: the claymore soon got caught in between the trident's prongs once again. But instead of a repeat of what happened earlier, a wheel of fire suddenly erupted around the king, grazing Sparda's shoulder as he jumped away.
Continuing with the offensive, Asgore quickly swung with the force of a booming thunder, pushing the Dark Knight even further back as he defended himself with his sword. He quickly returned that gesture with violent sweeping arcs, successfully managing to scrape the king's lustrous armor.
Crackling noises were heard as Frisk saw cracks forming on Sparda's barrier, slowly growing bigger by the minute as the battle continued. They quickly slammed their fist onto the cracks: it hurts like hell, but it looks like it slowly sped up the process.
Determined to get through, they have to make a difficult - and incredibly painful - choice.
Glowing violet swords floated around Sparda, as burning balls of fire did with Asgore. Whereas the two made their charge again, the violet blades and and balls of fire seemed to have a mind of their own, fighting their own battles which resulted in turning the room into a clash of violet and orange.
But somewhere during the battle, Sparda made a mistake: though small, he accidentally left a window of a chance. Picking up on it, Asgore quickly impaled Sparda through his abdomen, before a torrent of flames soon took over where the Knight himself stood.
The king of the monsters soon took this opportunity to regain his strength, unable to capture the man's soul as he was too fatigued to do so.
Right, after that was the most difficult part...
As he headed for the dark barrier, something in his mind caused him to slowly tense up and freeze. He quickly turned around and caught an incoming bkade with the shaft of his trident, but somehow the shaft broke into two, causing the king to stumble back.
The man who Asgore thought he cut down was still standing, even stranger was the weapon he now currently held: what was supposed to be a cumbersome, double-edge sword now became a thin, single-edge blade.
Strange, this blade feels familiar to the kind in those shows the royal scientist watches. What were they called again? Ah-knee-meh?
He brushed those thoughts aside as Sparda continued on the offensive. If he was slower before, then he's certainly faster now. He attacked swiftly and continuously, not allowing the king to have even a small moment to catch his breath.
Asgore panted as he dodged another barrage, he knew he was slowly running out of time. With one final act of desperation, a torrent of flames erupted from his hands and onto the Dark Knight.
But Sparda was faster: he moved his sword arm as quickly as he could, cutting apart the flames as he approached closer and closer. When he was confident enough, he struck with a large, sideways arc, leaving a large - though not lethal - gash across Asgore's chest.
Asgore fell on one knee, the king of the monsters has finally been subdued.
Epilogue
"I'm sorry" Sparda said, sheathing the single-edged blade. "I can't let you make the same mistake he did..."
"He?" Asgore questioned, putting his hand over the scar on his chest.
"I knew somebody once" Sparda looked over to the barrier that lead to the outside, "like you, he was a ruler. What he wanted to do was about to endanger so many lives, so I had to put a stop to him. Now do you understand why I have to do this?"
Asgore didn't respond, taking more of an interest on the ground rather than anything else. When he looked back to the man standing before him did he finally decide to speak:
"At least... spare my people, they did nothing wrong"
"As you wish" before he could bring down his blade onto the king, his swing came into an abrupt stop as the human child came in between them, arms outstretched. "What are you doing, child!? I nearly cleaved you in half!"
Frisk still stood with their arms outstretched, determined not to move away. The king himself was surprised by this sudden act of kindness, despite the child knowing full well that he was trying to kill them mere moments ago.
"Stand aside child, he's made his decision"
Frisk shook their head profusely, causing the Dark Knight to sigh in response.
"I see..." Sparda then proceeded to swing in a wide arc. To both of the king and the child's surprise, they found themselves unaffected by the attack. However, the sounds of crackling glass soon got their attention: as they turned around, they noticed that the containers had been broken, and the souls are nowhere to be seen.
"W-what are you-" before Asgore could finish, Sparda began swinging his blade in every angle. As he returned his sword to its sheath, the effects of the attack had finally registered...
And destroyed the barrier...
"I'll help you broker peace so your people may live" Sparda spoke, gathering their attention. "But I will not hesitate again to unleash my blade if the situation calls for it"
He then lent a hand to the king of the monsters "are we clear?"
Asgore then accepted the man's kind gesture, a small smile soon eventually formed on his face.
"Crystal"
AN: two Dads duke it out to see who's on top... yeah I'm most definitely high rn lmao
Anyways, just for some lore accurate shit, I'm using post-seal Sparda