All of Asgard was in a frenzy that warm, bright afternoon, for on that day, their beloved Prince Thor would amaze those lucky enough to travel to Odin's castle with a show of his power. Lady Sif had single-handedly trapped and caught a fearsome beast she had encountered in the forest, and had brought it back for Thor to fight for the people's entertainment.
This beast was much like a boar, but several times bigger, so as to stand nearly as tall as Thor himself. Its tusks were almost as long as its muscular body, and stained deep from the blood of countless hunters. Lady Sif had barely survived the chance encounter, and only by tricking it over a cliff, had she managed to knock it unconscious, and thus bind it and take it home. She could have killed it and brought it back as a magnificent feast, but, as she told her beloved, she decided she would present it to him as a gift.
They kept the beast in captivity for a week, giving the people of Asgard enough time to prepare for the journey, but on the eve of the day the fight was planned for, Asgard's second prince Loki entreated his brother to wait yet another week.
“But why, brother? The people expect the great fight to be on the morrow!” Thor was not pleased by this request, but because he loved his brother, he did not deny him outright.
Loki replied, “Dear brother, the beast is still extremely tired from its abduction from the forest. I have seen it for myself. If you fight it tomorrow, it will not be a fair fight. Do you not wish to give your adoring public the most thrilling show possible?”
The golden haired prince could have sent a servant to check on the beast's condition, but he believed Loki. Even though his brother had deceived him numerous times before, Thor trusted Loki this time because he could not imagine what Loki would profit from putting off the fight. And, perhaps because Thor was already in high spirits, he was able to remember all those times when his brother had indeed helped him out of love. He believed this was one of those times, and that caused him to embrace his brother with great love and gratitude, before announcing the change of plans to the people.
So the date was changed, and while this was disappointing to those who had already arrived, this gave even more citizens the chance to make the journey. It was, overall, a satisfactory decision for everyone, and Thor felt all the more noble for allowing his opponent the chance to grow strong again.
One week was just enough for Loki to make a journey of his own. While Thor entertained those who had arrived with days of feasting and revelry, Loki stole away on his horse and went to Jirginmandif, an old recluse who had taught Loki much in the arts of shape-shifting. After explaining his purpose to her and paying her an exorbitant sum, Loki took leave of her ancient house with his head filled with knowledge, and his pockets filled with the ingredients for a potion.
Once back home, Loki brewed the potion as he was instructed and stole into the stables in the middle of the night and released the beast. Since it had been despairing in its tiny pen for over a week, it was only too glad to tear off into the night, quite possibly never to be seen again.
Then, Loki drank the potion and locked himself in the pen, where he slowly transformed into a perfect copy of that terrible creature, complete with all its mighty strength and sturdiness. Jirginmandif had warned him that while in this form, his magical abilities would be rendered useless, except to turn himself back to his previous form. Also, he was warned that any great blow might force him back, so he must take great care. As long as his mind and his wit would still be intact, then Loki was not worried.
The next morning, Loki, in the form of that terrible beast, was brought into the great hall, where he would face Thor. The huge room had been cleared for these two opponents, and the spectators had filled to bursting the benches provided for them.
The audience gave such sounds of awe and amazement, that Loki found it difficult not to strut. But he reminded himself to behave as the monster he appeared to be, at least at first. Thor must not suspect anything.
And Thor did not seem to. In fact, he charged at Loki the second he entered the makeshift arena with a fierce lust for battle that would have terrified Loki were he not protected in that stolen form. At first, Loki acted as befitting his form. He roared and brayed and ran about in wild, mindless rage. He swung his head to and fro, and nearly sliced his brother with his fearsome tusks, while the audience screamed and cheered.
But he did not let Thor grab him. Unlike the monster that was meant for this fight, Loki knew his opponent very well. He was able to correctly predict when Thor would try to grapple him, or when he intended to punch his huge, craggy snout.
Soon the spectators were not cheering, but jeering. As much as they loved their prince and were eager to watch him display his might, they had no qualms about laughing at how he was now fumbling and tripping over himself. And the more they laughed, the angrier Thor became. And the angrier Thor became, the more fun this spectacle was for Loki.
For as much as he adored his brother, Loki also adored humiliating him. Thor was powerful and beloved in a way Loki knew he could never be, so sometimes, he just wished to knock him down a bit. And anyway, he did intend to pretend to die after a while. He would take a few hits from his brother and then collapse, making his brother the hero again. He just had to be careful about which hits to take.
But Thor's lack of patience destroyed such plans. For soon enough, he summoned Mjolnir and pounded the floor beneath their feet. The crowd erupted in approving, excited roars as every creature present shook from the impact. They were eager to see their hero redeem himself. Apparently blood was more important to them than fairness.
Now Loki was afraid, but he was not yet ready to change back, not in front of all these people. He knew he dared not allow that hammer to strike him, but he was not sure what he should do.
So this time, he took great care to run and dodge from Thor's attacks, and this time, the crowd did not laugh, but waited with bated breath, as they could see how tired and slow the beast was getting. It was only a matter of time now before its skull was bashed in.
But even armed with Mjolnir, this was still the same old, predictable Thor. While he took the time to raise his arm for a swing, Loki charged and ran one of his tusks through his brother's torso. He slid back out before the hammer could fall upon his head and scampered out of the way. Even with a gushing wound, Thor's bloodlust was far from sated. Here merely ripped off his shirt and used it as dressing. Then he came after Loki, completely berserk.
Loki's hooves slipped in Thor's blood as he tried to turn, and Thor smashed one of his tusks in pieces. Loki screamed out agony, his voice coming out natural for his form. The spectators erupted in a frenzy that seemed to drive Thor on, as if he weren't bleeding out of his side. In fact, he was grinning again, pleased to have regained control of this battle.
A few more minutes of scrabbling around, and Loki slipped once more. This time, he could not avoid being severely hurt. The hammer struck Loki in his massive rib cage.
This blow was severe enough to jolt Loki's form back to normal. The bulk of the felled beast abruptly transformed into the naked, battered body of Thor's brother. The second prince was alive, but barely. Blood oozed from a hole left by a missing tooth, and his torso was covered in vicious bruises. He struggled to breathe, much less move.
The audience cried out in shock, but Thor ignored them. He cast Mjolnir aside and fell to his fallen brother, roughly collecting him in his arms, even though doing so would only make Loki's injuries worse. He cried out in great distress and demanded to know why Loki had done this. Meanwhile, a group of guards were waiting to take Loki to the healing room.
Loki, unable to laugh or speak, merely smiled as much as he could, and looked to the guards. But Thor did not surrender his brother to them. He insisted on lifting his broken body into his arms and carrying him by himself, even though Thor's own strength was rapidly depleting from the wound his brother had given him.
The princes were both healed, and then promptly scolded by Odin for their foolishness, which could have robbed Asgard of both its heirs at once. Their parents were livid, Sif refused to speak to Thor for a long time after, and many that sat in the audience thought them both fools. But Thor could not remain angry at his brother. After all, he had entered that arena hoping for a thrilling fight, and Loki had given it to him.