@pdonk
"but then I really don't know how on earth Cestvs would manage to beat him."
I think Cestvs has the best chance of beating him, since he's the most agile (maybe Adonis aside). Someone as large as Loki would expend a tremendous amount of stamina when his powerful punches miss, as missing is FAR more tiring than hitting is. Sure, he's a superhuman lumberjack, but a lumberjack doesn't miss the tree, so it's not a strain he'll be used to. And Cestvs has powerful special attacks that could bring down even bring down even a giant like Loki.
I think Kamose will win, though. He's a boxer, and we've already had "David (a Jew) and Goliath" reference as foreshadowing. He has a much more compelling theme as well, that of thoughtfulness and honour in the face of his rash, thoughtless, opportunistic "comrades." His later defeat will be a win for him and his people due to the way he handles it, I imagine.