Author's Note: Thanks to duhorcommonsense for the follow.
Forn
It had already been hot in the rest of the palace, but it was even more so as Thor started into the fifty-feet wide and long throne room. Sweat beaded on his forehead as he, Loki and everyone else stopped on the outer-edge of the room in shock. Near-by, Father and the Einherjar were in the far corner, held at bay, by the Eldjotnar. Before them the nine and some-foot tall King of Muspelheim lounged on Father's throne. Surtur's cold, black-green eyes glowed in triumph as he spotted Grundsol, himself and Laufey. A terrified Daell sat hostage on Surtur's lap with an orange/red-skinned hand wrapped around his tiny throat.
Daell squeaked, "Father, help !"
'Father did say that Surtur was unpredictable. Well, he just kidnapped a child to steal a throne he doesn't need.'
Sandr roared, "Let him go, you monster !" and tried to rush forward. As he remembered the enormous fireball that Surtur had thrown at himself, Fandral and Grundsol he caught Sandr's arm. The red-haired, tan-skinned man jerked to an abrupt stop.
He hissed, "Sandr, it will not help Daell if Surtur burns you to death in front of him !" Then he actually hissed as Sandr stomped on his foot. Suddenly, Laufey started past himself, Sandr and Loki to walk down the dark-red carpet.
Loki exclaimed, "Father, no ! Let Thor handle this, it is his home, after all. You don't need to risk yourself."
It was Sleipnir and Hailfalla who lunged and grabbed hold of Loki. Their attempts to stop his love were useless as Loki simply started pulling them along instead.
Laufey's, "Be silent, Son." stopped Loki in his tracks half-way down the carpet. Their frantic acts just made Surtur laugh in disdain. He, Grundsol, Sif, Issflod and Sandr quickly moved to stand around the three lighter/middling blue-skinned Jotnar.
'What are we doing ? What is Laufey going to do ?'
The dark-blue skinned King of Jotunheim stopped five feet from Surtur. Laufey intoned, "Surtur Forn. What quarrel has the King of Muspelheim with a child ? Asgard itself, I can see. It produces people who are arrogant as they come and destructive as they leave - but a mere child ?"
Everyone, but especially Sandr and Sleipnir tensed when Surtur drew his finger across Daell's throat. Surtur tsked then said, "Laufey, Laufey, the child is nothing. The Asgardians stole not only Ymir's Casket from you, but your own son. You needed my help to return your precious Yfirloki to you, so why are you helping them now ? I find that far more of a betrayal than my conquering the all-powerful Allfather by threatening a child."
Laufey unsheathed the carven ice-sword on his belt and spun it a few times. "I am helping them because I will not have anyone, even an Asgardian, go through what I did. You have conquered no one Surtur, your Eldjotnar have surrendered and the rebels are captured. Let the child go and you just may return to Muspelheim yet."
A chilling laugh left Surtur's lips before the ancient one flicked his free hand carelessly, a circle of fire sprang up around them. Above the roaring of the fire, Surtur's voice echoed. "As I have the means, why do I not just kill the House of Ymir and the House of Odin at once ?"
Sleipnir started whimpering and shaking as the fire flickered. Ice covered the rug and floor as everyone pressed against each other, but like the library the fire refused to go out. Loki snarled, "No !" before a huge gust of icy wind and snow burst out of from his love.
The fire died in an instant and Sleipnir shifted into horse-form before racing towards Father, the Einherjar and the Eldjotnar. Sleipnir reared and slammed both his front and middle sets of hooves into one of the Eldjotnar's chests. Hailfalla and Issflod rushed to Sleipnir and the others aid.
Meanwhile, a stream of lava was leaving Surtur's hand and a stream of ice was leaving Laufey's. Surtur's bright-red/orange fire was slowly, but steadily being forced back by the pure white ice. 'Laufey can't keep that up forever ! If it gets too close the ice will freeze Daell. We can't help without hurting him either.'
Sandr rushed past Laufey, they followed and Loki threw a hand up before another gust of wind sprang up. The gust disrupted Surtur's fire and without that to stop it Laufey's ice slammed into the fire-giant's face. Sandr leaped up the steps three at a time, to chop through one of Surtur's knees with his axe. In response, the King of Muspelheim punched Sandr who went flying off the throne to crash into the marble floor. Seconds later, Sandr was scrambling for his axe.
Not knowing what to do, he turned to look at the rest of the fight. It horrified him to see that an eldjotun had Sleipnir, still in horse-form, in a head-lock. Again, without thought Mjolnir left his hand to slam into, and through, the eldjotun's head. Grundsol stabbed an eldjotun in the back of the thigh before Father stabbed it in the chest with Gungnir. Hailfalla an ice-sword extending from his arm was parrying a fire-sword. Mjolnir returned to him, he ran, jumped and landed on a fallen eldjotun's back to slam the hammer into the eldjotun's neck. When he looked up, the Einherjar were swarming the last eight-foot eldjotun.
Sleipnir gave a shrill scream of fright. It prompted him to turn and see what was happening with Surtur. Loki was hanging off Surtur's right arm which was turning black with frost. Surtur snarled and punched Loki in the face with a flame-covered fist. Loki flew back and crashed into a pillar cracking it in half from the force.
As he sprang off the eldjotun's back, he flew toward Loki and the pillar. While he did that, Laufey sprang to the throne's arm to slam his sword flat down on Surtur's arm which shattered. Dimly, he noticed Daell scrambling away to fall down the throne's steps. Jotunheim's Crown Prince was barely conscious, his head lolling amid shattered stone. Worriedly, he knelt, dropped Mjolnir and scooped Loki up. Long-eyelashes fluttered, then he noticed an imprint of Surtur's knuckles seared into Loki's left cheek. It looked like Loki's nose had broken as well.
Laufey suddenly roared, "Surtur Forn is dead !"
That prompted a slightly pained smile from Loki. Thor asked, "Shouldn't you heal yourself, love ?"
Loki shook his head and stated, "Father has scars from a mikilbjorn, it was the first one Father killed on his own. I helped to kill Surtur and I'll keep the burns to prove it."
Finally, he twisted to see Laufey holding Surtur's severed head on a plate of ice.
'Laufey already had scars ? Is that what those were ? I thought they part of his face tattoo. Is Loki going to get a tattoo now ? That would be interesting. Father, Sleipnir, Loki and I can go back with the others to the library to check on Mother then I can finally talk with Hailsturm and Ennsturm.'