Sunday, August 16, 2009

Using non-standard materials for weapons and armour

In honour of Dark Sun being the new setting, I thought I would post the rules I use for non-standard materials being used for weapons and armour. Athas is a world where weapons are made of wood, bone and obsidian more commonly than steel, so this seemed fitting to post.

This is to deal with issues were different material weapons sometimes have confusing rules, ie a flint arrow versus a steel arrow. Sometimes these rules are ignored, and I state openly that rules for different materials should only be used in settings where it matters. If its a medieval Europe game then you don't need to crack out these rules for the one time a warrior picks a bronze dagger from a work bench and throws it. But if its an Ancient Greek setting and there is a mix of bronze, iron and steel it might, and if its a conquistador mesoamerican setting then the comparative power of steel makes it paramount to have these rules.

Materials are all given a few different criteria: Hardness, Sharpness, Weight and Breaking Point.

Hardness is the main factor for different materials. When comparing a piercing or edged weapon versus hard armour (mail or plate for instance) you note the difference in the hardness ratings. For example with steel weapon versus bronze armour its a rating of 1. The effectiveness of the armour is thus worsened by 1 for Damage Reduction for slashing weapons, for piercing weapons the number is different. If it had have been bronze weapons versus steel armour the armour would have its DR Increased by 1.

Sharpness is a number that is used for slashing and piercing weapons versus unarmoured opponents. It is a direct modifier to damage. A wooden sword would have a sharpness of -2, but an obsidian knife would have a sharpness of +1. Steel is used as a baseline (+0)

Weight is used as both a reduction (or increase) in weapon speed (based upon size). For blunt weapons it can also be an increase to damage.

Breaking point is the amount of damage the weapon can give or receive in a single blow (before multipliers) before the weapon risks damage. So a bone spear might shatter easily, a bronze sword occasionally bend and a lead mace may do great damage once, but its mace head will quickly be deformed into uselessness.

These rules both increase flavour in appropriate settings and offer new types of rewards beyond "magic" items. A mithral sword may be mundane, but its stronger material, lighter weight and razor edge make it a great reward on its own.


  1. Gimme a table now! I wanna see what materials you use and how you applied these.

  2. Well, these played most heavily into a meso american setting (first flint as superior to starting bone and wood weapons, then obsidian as superior to flint before having steel become available, which in Most ways was superior to obsidian, except against unarmoured foes)

    But the last time these came into play heavily was with survivalism, the band of heroes trapped on an island making crude weapons and traps to thwart the attacking soldiers. Wood spears and a slashing blade made from a monster horn.

    So with the wooden spears, wood had a hardness of 2 to bronzes 4. As a piercing weapon this meant the bronze armour gave +4 damage reduction (already 5 versus pierce) and spears only did a 6 damage before stregth. So only very strong individuals could even stand a chance of doing minor damage through the armour with a wood spear. This meant that being piercing weapons, they had to rely upon getting a critical hit and bypassing armour.

    The horn (enamel) was better suited with hardness of 3, being made into slashing weapon it only added +1 (3 to 4 for bronze) to the armours effectiveness.

    Other times this comes up are superior weapons (mithral has a hardness of 6 and a sharpness of +3, making it harder than steel and sharper than glass), Silver Weapons used in regular combat and with "treasure" weapons, such as in desperating using an ornamental golden dagger to stab someone (which mangled the dagger in a single shot and did not pierce the steel armour)