Author's Note: This tale is in response to another prompt on the Norsekink Livejournal. To avoid spoilers (for anyone who doesn't want to search it out, anyway), the relevant part as an introduction of this story is as follows:

"The events of the Thor movie start off as usual, there's the fight on Jotunheim, they return home, Thor and Odin yell at each other, Loki tries to interrupt but gets growled into silence. But what he was trying to tell Odin was that he's really not feeling well."

So begins an AU!

Prologue

How had this happened? How had he lost control so utterly?

It should never have come to this. That guard should be flogged for taking so long. Or was it Odin who had delayed? Why had he done that?

Loki's stomach roiled, hot and painful pressure rising up his chest, making him short of breath. His one bare arm tingled… sensation was giving way to a deeper throb as if he'd wrenched it badly fighting. Worse, it was growing, moving up the exposed arm into his neck, up into his head. He was dizzy; his head throbbed as the voices in the Observatory rose.

"Father - "

Odin snarled so furiously that he recoiled. Why such rage? It wasn't Loki who'd provoked this – yet, it was. He'd goaded Thor; he always did. Did their father know how Laufey's men had reached the vault? Had he found out? Did he know what Laufey had told Thor?

They had dismissed him again without a second glance, not even noticing or caring what was troubling Loki. They were shouting at each other with such venom as never before. Odin and his firstborn had like tempers, but not this, never this. It was like a dream, Odin advancing on Thor, who he'd so lauded and approved, tearing the magical badges from his armor, the fine metal and leather falling to pieces without the Allfather's endorsement. Thor looked as dazed as Loki felt – Loki's head felt as if it were filling with hot water – he couldn't breathe properly –

Over Odin's angry tirade came another voice: Heimdall's.

"Allfather!" The Gatekeeper sounded almost… alarmed?

Lost in a rising tide of hot, white light, Loki was only vaguely aware of the dark figure now before him – the grip on his arms nothing compared to the burning throb coursing through his veins. What had happened? What was happening?

Thor's voice… frightened, from somewhere in the distance. "Loki?"

Over Heimdall's shoulder, he spied one blue eye. Now Odin was looking at him. Now he took notice. But Loki could not even speak properly. His famed silver tongue clumsy and swollen, he could only mumble the question foremost on his mind: "'m I cursed?"

Then the hot white fog rose up and swallowed him.

Thor would have forgotten all about his impending punishment but for Odin's arm blocking him when he tried to rush to Loki's side. For a moment, the horror on his firstborn's face nearly weakened Odin's resolve. But… No.

Thor had brought this about. He had to suffer the consequences, including the wounds to his friends and his brother. Stripped of his power, he could not shove past his father to reach his fallen brother, and Odin gave him one last glare. His intent dawned on Thor, who cried out, "Wait!"

But Odin hurled him into the Bifrost. Let him learn his lesson, perhaps faster knowing his actions had brought Loki to harm, and forced to wonder what the end result would be. Mjolnir followed, its power sealed with a whispered enchantment, and then Odin turned his attention back to his younger son.

"He was wounded?" Loki hadn't said. Why hadn't he spoken up? The left arm of his armor was gone, the edge frozen and cracked away as Volstagg's had been, but there was no corresponding frost burn on Loki's flesh. Odin knew why, and doubted it would take Heimdall long to work it out (assuming he hadn't before now.)

The Gatekeeper studied Loki's arm. "He said not, but…" He paused, then rested his fingertips on what at first seemed a small bruise, just below the elbow. It was a puncture, the flesh around it discolored – or rather, blending back into what Odin knew to be its natural color.

Odin's blood ran cold. The Aesir might sneer that the Jotnar had no subtlety in war and weaponry, but some of their crafts were all but invisible and no less lethal than the sharpest mace of ice. The generation who'd fought the last war had ample experience with these crafts.

Ironic. Had such a dart struck Thor or any of his friends, they'd have died in minutes. But Odin dared not gamble that the poison would not kill a Jotunn. "I must get him to the healers." He hauled Loki into his arms and carried him out to lift to Sleipnir's back. It took more effort than it should have, to get himself mounted and the boy secure against his chest.

One son banished for his stupidity, the other fallen from a poisoned wound. What an end to this day.

As if the hour were not growing dark enough already, Frigga was waiting when he carried Loki into the healing room. "What happened?! Where's Thor?"

"I'll explain later," Odin grunted and laid Loki down as Eir hurried to examine him. The master healer's eyes narrowed at the dart wound on Loki's arm, and then flashed up at Odin. Of course, she knew Loki was no son of his blood, nor even Aesir, after all the years she'd spent treating his and Thor's injuries. Odin had never spoken of it to her directly and doubted Frigga would have done, but Eir would never have mentioned it unless it truly mattered to healing him.

It did now. "Were he born of Asgard, he would have died instantly," she said quietly. Frigga sucked in her breath and sat down on the edge of the bed. Eir went on, "Jotnar darts are steeped in magic poison. They are meant to kill the enemy swiftly, but I fear he's not immune. The tales we have of earlier days speak of these darts being the favored weapons of assassination between feuding houses."

Frigga felt Loki's arm and face as he shifted restlessly. "He's feverish, but his heart beats strong for now. Perhaps it's not the same poison. Why would the Jotnar strike at Loki with such a rare and lethal dart?"

"Perhaps he wasn't the target." That thought had already occurred to Odin, but it was Eir who gave voice to it. Frigga shut her eyes. Eir looked from the queen to the king, then back again. "I will do all that I can."

Frigga opened her eyes and then stared at Odin. "Now tell me the rest. Where is his brother?"

To be continued...

Coming This Weekend: Frigga gets bad news, Loki gets worse news, and the consequences of the fight in Jotunheim continue to spread.

I hope to have updates every few days. Please don't forget to review!