Dang. That was good.
Beginnings are always the hardest, but you picked up speed with the alliance. If I haven't mentioned it yet, you're dialog is excellent. When your story begins to flag, your dialog brings it right back. If there is any feedback I could give from here and other pieces of your work I've read thus far - Deeper investment in dialog would only strengthen your story.
Most writers fall into the trap of info dumping (Story background) in a paragraph or four, and all that does is put your reader to sleep and weakens the thread of the story line, but delivered in conversation can strengthen it. Of course you have to avoid droning on and on, but with your grasp of dialog and knack for portraying the speaker's emotion, I think you could describe a bit more of what's going on around the action.
I don't know why I care, other than I really got sucked into the story as it went on, but the "Curse your sudden but inevitable betrayal!" that I was waiting for from Tibalt didn't get a chance to materialize and the allied battle didn't seem to end but instead faded into the fog of war. I guess I would have liked to see the Bret's routed after the fall of their general and the flanks of the Empire wheel to destroy their ally/enemy - and have Bjorn pulled into the Gods' Hall as a boon for a job well done after said betrayal, with a little good ass whippin' by the Valkyrie who comes to claim the heroes.
But I guess that would sort of required more than just four to survive, since 4 guys don't even make a rank unless they're the size of rat-ogres. :laugh:
All said though - Nicely done!