In the recent threads on armor and armor piercing on the Bay12forums, the game calculates and checks for fracture stress and impact stress when crossbow bolts i

In the recent threads on armor and armor piercing on the Bay12forums, the game calculates and checks for fracture stress and impact stress when crossbow bolts impact armor. So for example the game will test to see if the impact_yield, and further research in the threads below reach conclusions such as : " the IY (impact_yield) deflection mechanism is related to armor density, armor thickness, bolt size, bolt impact yield, bolt contact area, and the difference between mail and plate at larger contact areas." Armor density takes from armor material - Iron/Steel/, as does impact_yield. Here is the thread where the initial !!Science!! on whether bolt weight made an impact on their lethality - [Dwarven Research: The Effect of Bolt Weight on Crossbow Performance](http://www.bay12forums.com/smf/index.php?topic=115683.0 http://www.bay12forums.com/smf/index.php?topic=115683.0) The results were converted on reddit into a LaTeX PDF, which is excellent reading - http://dl.dropbox.com/u/2891221/DF%20study.pdf http://dl.dropbox.com/u/2891221/DF%20study.pdf This led to the follow up: A Comparison Study on the Effectiveness of Bolts vs Armors LaTeX - http://dl.dropbox.com/u/2891221/DF%20study%202.pdf http://dl.dropbox.com/u/2891221/DF%20study%202.pdf Thread - http://www.bay12forums.com/smf/index.php?topic=116151.0 http://www.bay12forums.com/smf/index.php?topic=116151.0 The underlying algorithm for impact_yield deflection on page 11 was: " Algorithm: 1. The projectile is hitting the creature on a body part protected by a piece of rigid armor (i.e. bolt hits steel breastplate). 2. Multiply the armor's LAYER_SIZE by the projectile's CONTACT_AREA, and round the result down to the nearest 100. The exception is that you round up to 100 instead of rounding down to zero if the result was less than 100 (i.e. 20x2=40 -> 100). 3. IMPACT_YIELD = (800/157) * ARMOR_SOLID_DENSITY * (step #2 result) / PROJECTILE_SIZE " And thats to test if a bolt deflects on impact with armor. Penetration causing severing of tissue, blunt damage causing bruising are also possible depending on the Armor vs Bolt combination. And this is a minor sub part of the game which most people don't see.