>>96076594
If you're going based entirely on gambits and how good their characters/duelists would be, I think Space Wolves are definitely up there just for the sheer fact they can lock someone in a cage match and they can't leave until either of you actually die, and they have access to the Great Frost Blade which isn't a bad dueling weapon. White Scars' could also be a fun choice; their gambit seems like it could be interesting, since you can basically gamble winning the iniative with the strike high, strike low gimmick they have which turns every power fist duelist into anime protagonists that can smack the enemy before they even blink. They also have that whole japanese/oriental vibe to them which is basically begging for cool 1v1's