How about to introduce automatic bounty, which will be computed from taken HPs during aggressive fights? That means when you initiate a duel and win, price on your head will rise, when you lose non-aggresive duel (you were attacked), price will go down. When you lose aggressive duel, bounty will stil raise, but only very slightly. Increase should be computed from money stolen, HPs taken - HPs lost, double rise/double drop when you KO someone respectively someone KO you.
More head hunting duelers chasing "bad guys" which stolen too much gold coins or killed too many people
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