Dueling (3.5e Variant Rule)
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This rule is intended for formal challenges- the type a Knight might give if another character seriously offends him. The intention is to give several variant rules that portray the different traditional types of duel.
 Variant 1: First Blood
This variant is quite simple. The duel is fought as a normal combat, but ends as soon as either character draws blood (deals lethal damage to the enemy). The character who caused the damage is the winner.
 Variant 2: Body blows
This variant represents a less dangerous form of duelling, where the two fighters keep bashing away at each other until one of them can't go on from the fatigue of numerous blows on their armour. This duelling variant uses a modified Armour Class rule. Discount the character's Armour modifier from the base AC, but not the shield modifier, to calculate the "body blow" AC. Any attack that would hit on the body blow AC but not the full AC deals non-lethal damage. Continue fighting until one duellist either falls over or yields. (This variant makes the Knight class from PHBII the consummate master of the duel... just as it should be!).