Material Hardness

Hardness of Materials (Optional)

Materials come in varied shapes, sizes, and compositions. Sometimes, it is important to be able to quantify the physical properties of a given material. It is important when artisans want to craft items, oftentimes to be enchanted or empowered by psionic energy. Further, mundane materials must have a basis for how much damage reduction and durability (read as hit points) they possess. Materials presented here have broad groups, and GMs have to make decisions where materials not described below fall into the overall scope of a given campaign. Further, supernatural metals like mytheril and admantite exist in fantasy games. These fantastic metals have to be quantified to provide them with the respect they deserve. There are two categories listed below: Material Hardness and Material Durability. Hardness focuses on a given material's Universal Damage Reduction (UDR), and Durability provides hit points for a given material. Although real-world estimations are used, the numbers have been adjusted to fit into a fantasy setting.

For example, a mining cart primarily constructed of brass (20%) and iron (80%), which has a total material volume of 2 cubic feet, would have roughly the following specifications:

Construction Data Weight HPS Hardness

530 lbs/2 cubic ft of Brass * .2 = 212 lbs 4 5

480 lbs/2 cubic ft of Iron * .8 = 768 lbs 19.2 6

Totals: = 980 lbs 23 6

Thus, a mining cart hit with a fireball which does 15 points of damage would ignore the first 6 points of damage and suffer a total of 9 hit points. Though it would be severely damaged, it is not totally destroyed.

Of course, superior construction can offer the cart +2 hit points (engineering); if the cart was full of, say, 1000 lbs of ore, it would have +100 additional hit points.

Example: Doors (4 x 6) ft in size and 2 inches thick (6 cubic feet in volume).

Construction Data Weight HPS Hardness

Pine – 25 lbs/ cubic foot 150 lbs 6 * 3 = 18 2

Oak – 50 lbs/ cubic foot 300 lbs 6 * 6 = 36 4

Iron Bound Oak – 80 lbs/cubic Ft. 480 lbs 8 * 6 = 48 5

The same fireball hitting these doors would destroy 72% of the Pine door, 30% damage to the Oak door, and 21% damage to the Iron Bound Oak door. Of course, there will be a chance that the door catches fire for additional damage.

How is it that an iron mining cart has fewer hit points than a wooden door and would be almost completely destroyed by the same fireball? Something must be wrong. Well, true. Area affect damage is applied across the entire surface of a given object. Therefore, things look slightly different when we look at the damage applied in this manner.

First, remember that damage is applied based on a single individual or rather 150 lbs, 6 ft in height, which would have roughly a 20 square foot surface area.

In example 1, the mining cart would have approximately a 65-square-foot surface area. Or just over 3 times that of a human, though it would still possess the same number of HPS of 23.

Thus, the area affected damage is applied 3 times and applied against the Hardness 3 times. Base Damage: 15 x 3 = 45, subtract the Hardness 6 x 3 = 18 leaving 27 points of damage – the cart is totally destroyed.

In example 2, the oak door would have roughly a 50 square feet surface area, 2.5 times that of a human.

Base Damage: 15 x 2.5 = 37; subtract the hardness 4 x 2.5 = 10, leaving 27 points of damage. The door is 75% destroyed – not accounting for additional fire damage after the fact.

So, in essence, larger objects can be damaged more if we follow standard physical laws. However, no one in the game wants to do calculations during combat. Thus, we can simplify the damage to objects by comparing the size factor. For NON-LIVING objects, each size category larger than a human the object suffers double base damage (after the subtraction for material hardness). This only applies to Area of Effect damage.