Trait list, and my take on them. Warning - very long.

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GoodCommander/BadCommander

Traits that effect command shouldn't be added - why? Because command is far different then actually fighting. Not everyone who was a brilliant commander was a brillaint fighter, and not all brilliant fighters were good commanders - in short, it's far to situational to give any defintive ground as to why it gives a bonus.

Drinker

It's possible this one could give a penalty - fighting drunk is likely to get you killed, and alcohol thins the blood, meaning you will bleed more easily.

Feck

Besides the humor interjected in a fight description, I am not sure how well smack talk translated during a duel, so...

Arse

Definitive penalty to combat, possibly increasing the chance of failing an attack or defense

Girls

I honestly can't see this becoming involved in a duel at all...

Sobriety

A Bonus to dueling, for keeping a clear and level head?

GoodAmbusher/BadAmbusher

This may or may not give some form of slight of hand bonus, enabling you to "cheat" in a duel, or suffer from not understanding how to cheat in the case of badambusher.

Disciplinarian/BadDisciplinarian

Could possibly give an excellent bonus to insure that your actions almost never fail, since the character has trained very, very hard. An opposite effect for being a bad one.

Good/Bad Seiger

Same issue with the GoodCommander/BadCommander traits

Brave/Coward

Bonus/penalty to attack, or simply a similar bonus to Disciplinarian? Nonetheless, an important trait in a duel.

Slothful/Energetic

Changes in priority when attacking and defending, possibly allowing energetic avatars to be able to reroll a die, with slothful being forced to reroll their highest die. It could also translate into a loss of a die or an increase in number of dice. powerful, and usually rare trait.

Berserker

Definite bonus to attack and penalty to defense

Xenophobia/Xenophilia

No effect in a duel, except some smack talk...

PublicFaith/Atheism

I'm not sure this would ever factor into a duel, besides how the avatar ended up in it.

Good/BadAdministrator

Unless it's a duel to see who can transcribe the bible faster...no bonus or penalty.

Inspiring/BoringSpeaker

A possibility for morale, if it's involved - otherwise, no effect

RhetoricSkill

Bonus only if we can bore our opponent to death

StrategicSkill

Possibly a larger die size as a benefit.

TacticalSkill

Allows you to reroll those dice if they are not to your liking - limited by your level in this trait. Possibly being able to reroll one die per round, per level in the trait.

MathematicsSkill

Again, no effect in a duel

PoliticsSkill

Isn't that why we are fighting the first place? Because you have none?

LogisticalSkill

No effect

Rabblerouser

Great way to get the crowd on yourside, otherwise not sure this would help.

VictorVirtue

Same as Rabblerouser, although it may give some kind of intimidation factor

Epicurean/Stoic

Have no clue how this would work out, both only effecting loyalty and the ability to be bribed.

Austere/Aesthetic

Similar issue to Epicurean/Stoic

Ignorance

Lower success rates, but with a bonus to morale?

Gambling

Reroll everything, but only once per duel

SpyMaster

No foreseeable benefit, except for trying to cheat or be able to negate cheats

AssassinMaster

Understanding how to kill someone is of a great benefit - possible attack bonus, or ability to ignore your opponent highest die roll.

CounterSpy

This would probably work better for being able to catch cheaters then SpyMaster

AssassinCatcher

Possible defense bonuses with the ability to ignore your opponents highest attack roll?

High/LaxPersonalSecurity

Defensive penalty/bonus?

Trusting/Paranoia

Same as above

Liar

Increased ability to "cheat"?

Embezzler

This isn't so much a good trait for dueling, as a good way to end up dueling

DeceiverVirtue

High potential to be a good "cheat" trait

Upright

Good anti-cheat trait potential

Corrupt

Another good cheating trait, although this one could have the possibility of backfiring compared to DecieverVirtue

Authoritarian/Nonauthoritarian

I don't see this coming into play ina duel very much as a deciding factor

Disloyal/Loyal

Again, not sure

Cuckhold

Your not fighting with THAT sword...so, no effect

GoodFarmer

Trimming a plant is a bit different then trimming a bush - no effect

GoodMiner

No idea how on earth this could help...

Good/BadEngineer

Catapults and Seige Towers are bit of a no go in dueling...

Good/BadTrader

This would never come into play in a duel

Just/Unjust

No bonus beyond what each trait gives, although this may count if we also include regular jousting for a morale bonus

Harsh/LenientJustice

Same as above

Harsh/KindRuler

Same as above

Good/BadBuilder

Not important during a duel, unless you designed the arena in which your fighting

Generous/Miserly

If we involve a crowd, this is a definite morale bonus

Noctophobia/philia

A time of day bonus/penalty? only if your opponent is foolish enough to challenge you when you have advantage

Perverted

This, should, never come up. If it does, then...I think we will have far greater issues then deciding who is the winner of the duel...

Scout

Gives an opening duel bonus to attack and defense

BattleScarred

Possibly a trait which reduces the randomness of your own rolls? And adds a Hp bonus?

Good/BadInfantryGeneral

You understand the dynamics of an infantryman and the tactics inherent in dismounted combat in the medieval era - I say a signifigant dueling bonus, or penalty

Good/BadCavalryGeneral

Same as above, but only for Jousting.

Fears and Hates "InsertFaction"

No effect

Inbred

Your momma jokes may be taken to a whole new level, but your comabt skills won't be - no effect.

Handsome

A pretty face isn't going to duel for you, but may get the crowd on your side

Ugly

If you have a third arm or second head, this may help. otherwise, I see no effect

Fertile

Nope, not going there...

Infertile

No effect in dueling

Good/BadTaxman

No effect

Divorced

Lots of openings for humor, little openings for actually effecting who is going to win - no effect

Good/BadRiskyAttacker

Should give a hefty bonus/penalty to attacking, with the penalty of making it more random.

Good/BadRiskyDefender

Same as above, but gives a bonus/penalty to defense, and a morale bonus/penalty instead of making it more random

Pragmatic/Superstitious

Not sure what this would do...

ExpensiveTastes/Cheapskate

Same as above...

Hypochondriac/HaleAndHearty

Modifies Hp? and Morale?

TouchedByTheGods

No clue

Sane/Insane

Not sure

Deranged

This is probably one to leave alone, since it's very subjective

Bloodthirsty

Attack Bonus?

Haemophobic

Attack Penalty?

Anger

This could grant a bonus to damage - where once you did only 1 damage (to morale or HP) per success, you now do 2, at the cost of making your attacks and defenses more erratic.

Lewd

No effect

Prim

Anti-cheating effect?

IndecisiveAttacker

Attack penalty?

Intelligent

A small, but general bonus to everything

Despoiler

Unless your fighting a Venetian or playing American Football, there really is no need to sack your opponent...

Genocide

This shouldn't effect the outcome of a duel

NaturalMilitarySkill

Unsure, but possibly a similar effect to having "Intelligent"

ForcedReligious

No effect

CrusaderHistory

Hmmm...a morale bonus?

BattleDread

Enhanced ability to cheat? Ability to reduce your opponents morale?

BattleChivalry

Exact opposite of BattleDread?

StrategyDread/Chivalry

Same as above?

CaptorDread/Chivalry

Same as above, or not involved at all?

RansomChivalry/Dread

Same as above?

Good/BadArtilleryCommander

Again with the catapults! No means no!

Good/BadGunpowderCommander

Cannons included!

Cursed

The dice usually decide this anyway, so - no effect

StrickenSilly/Serious

Possibly allowing you to use a Champion with no penalty?

Gregarious/Introvert

Another crowd pleasing trait, possible morale bonus

Dis/ContentGeneral

No effect

WifeIs "etc"

No effect

FactionKiller

No effect

Good/Bad Diplomacy

Obviously didn't work before you ended up in a duel...

Legacy traits

No effect

TourneyKnight

Good for Jousting, and for morale

AcademyTrained

Maybe reduce the randomness of your dice?

GloriousFool

Unsure - most likely no effect

TooOldtoFight

Ability to use a champion without penalty

Senile

Same as above