I realise that having re-read it - it was more of vaguely hamilton related rambling rather than an explicit question! XD

I guess I was wondering what spells could or would be used in an honour duel?

I guess if one was effectively throwing away your shot (i.e making your point but not trying to kill someone) you could disarm them, or if you were actually so outraged as to want to hurt them like Eacker who killed Hamiltons son, you might actually want to hurt them, so a spell that causes blood loss would seem to be the make the most sense - to introduce the chance that you MIGHT die during the duel.