Lethal/Nonlethal Combination Damage (3.5e Variant Rule)
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Lethal/Nonlethal Combination Damage
Different weapon types in the vanilla D&D 3.5e rules do not normally do much except for foes having damage resitances to certain damage types. Also in vanilla D&D, above certain levels, being between -1 and -10 HP would be almost impossible to achieve and as such, combat rarely ends with one side having some number of unconscious. These rules introduce a lethality score ranging from 0 to 4 depending on the type of damage in order to help incorporate a nonlethal damage percentage for attacking.
Lethality scores are as follows:
4 -> Perfectly lethal
3 -> Near-perfectly lethal
2 -> Averagely lethal
1 -> Somewhat lethal
0 -> Nonlethal
These base damage types have lethality scores as follows:
Piercing -> 3
Slashing -> 2
Bludgeoning -> 1
If a weapon has a lethality score of 3, the damage is split with 25% of its damage being nonlethal damage (rounded up or down at the player's wish) with the other 75% being lethal. If a weapon has a score of 2, the damage is split 50% for each type, and a score of 1 is 75% nonlethal. If a player rounds one type of damage up, the other type must be rounded down.
If a player uses a nonlethal attack (usually with a -4 penalty), the weapon's lethality score is subtracted by one. A lethality score of 4 is usually given to purely magical damage (i.e. not magical weapon damage) and isn't normally fit for providing any sort of nonlethal damage, though certain nonlethal spells do exist, and thus have a lethality score of 0. All critical hits, unless a nonlethal attack is declared beforehand, have a lethality score of 4.
If a creature has a nonlethal immunity, due to its inability to distinguish from all weapons of lethality scores of 1 through 4, such weapons are treated as if they have a lethality score of 4 when attacks are made against it.
As a special case, a sap and normal unarmed attacks have a lethality score of 0. At the DM's option, certain magic weapons might enhance or detract from a lethality score.