Well, alright, I'll post this here first, adhere to you guy's advice, and then maybe proceed to put it into the actual fan fiction section.
Okay, here's some critique for you!
Watch out for spelling and punctuation. For example, "a Imperial Legion engraved dagger" should be "an Imperial Legion engraved dagger" (though stylistically I'd probably change it to "an engraved Imperial Legion dagger"). "It's knees buckle" should be "its knees buckle." "Khajiit," not "Khajit." And always end a line of dialogue with punctuation, whether it be a period or a comma to continue the scene: "I suppose you're right, Torvald," Bjorn said.
You switch between present- and past-tense narration a lot, sometimes within the same sentence. This should definitely be fixed. Choose one and be consistent with it across your entire work.
While it's good to introduce your protagonist to your readers, a laundry list of facts about him may not be the best way to do it. The golden rule of writing is to show, not tell. For instance, instead of telling us that Torvald carries his father's old blade, you could work it into him skinning the elk: "Torvald dug his father's old dagger into the hide of the elk. He sliced away anything that could fetch a coin at the Whiterun market, wondering if his father had ever used it for the same purpose, or if it had only tasted the blood of elves in the war that had killed him." That shows us three things - the blade used to be his father's, his father had fought in the Great War, and he died in battle - without interrupting the flow of action in favor of exposition. Similarily, when Torvald meets Bjorn in the inn, instead of telling us that they grew up in Ivarstead and were close friends, you can show us in their dialogue: "Torvald! Old friend! How did I know I'd find you in a tavern? Come, have a drink. This mead is even better than what we used to slug down at the Vilemyr Inn when we were lads!" (This, of course, presumes the reader has played Skyrim and will know that the Vilemyr Inn is in Ivarstead. Whether you want to write for an audience who does or doesn't have a working knowledge of Skyrim is a whole other beast, which has been discussed
here.)
I would avoid having your characters address each other by name as often as they do. This is a very common mistake writers make that quickly takes away from the realism of their dialogue. Real people don't talk like that. The only reason we typically say the name of the person we're talking to is to call to them or to get their attention. But during a conversation with that person, we rarely, if ever, address them by name, especially not in every other sentence. The only time I feel it fits in Torvald and Bjorn's conversation is when Torvald first enters the inn and Bjorn calls out to him, and when Torvald says, "Dammit, Bjorn."
Other than the name-dropping, I think your dialogue is strong, not awkward or dull at all!
I like the origin of the name of the Blackblood Marauders. And I like how, at the end, you see what this entire prologue was about - how the Blackblood Marauders began, rather innocently, with one friend helping another out of some trouble. It gives purpose to the prologue, and that's exactly what every scene, character, and plot point in a story should have: purpose.
All in all, I think this is a great start to a story!