Dark Heresy 2E Damage Modification

(By the co-writer and editor known as Tanta Formidda)

Overview

One of my biggest personal gripes about Dark Heresy, Only War, etc. is the damage; it just feels too random to me. A normal human should not be able to survive a hit from a plasma gun, but a normal street thug (wounds 9 TB 3) has a 40% chance of doing so. In addition to this, I personally really like the damage system in FFG's Star Wars line, where each weapon has a base damage that is increased by rolling successfully. In light of these two things, I decided to make a conversion mod for making Dark Heresy's damage system function in a similar way.

Basics

Each weapon changes its damage profile from Xd10+Y to Y + (4 * X)- In less math-y terms, each weapon has a base damage rating of its original damage modifier plus 4 per d10; as examples, a human sized bolter would have a base damage of 9 (5 + (4 * 1)), while a melta gun would have a base damage of 18 (10 + (4 * 2)). I chose 4 because after about an hour of testing I felt that 5 was a bit TOO lethal, but that is of course a matter of personal taste; one of Dark Heresy's selling points is how deadly the combat is, after all. Pen is unaffected.

Once an attack is successfully resolved against a target, it's time to calculate damage. This is simply the weapon's base damage plus the Degrees of Success on the attack. As an example, if an acolyte fires a stub revolver (base damage 7) at a cultist and scores 3 degrees of success, the attack would hit for a total of 10 damage. 

Weapons also have a multiplier rating equal to the number of d10s they would roll (e.g. a lasgun has 1, a frag grenade has 2, an autocannon has 3, etc.). This rating multiplies the degrees of success by X; in the example above, if the acolyte fired a melta gun instead, they would add 18 (base damage) to 6 (2 * DoS), reaching a total of 24 damage.

Since weapons no longer roll d10s, Righteous Fury is instead generated by the attack role when the attack roll results in consecutive numbers (e.g. 01, 12, 23, 34, etc.).

Traits and other things

Accurate - Instead of giving a weapon additional d10s, accurate increases damage by 2 per DoS rather than 1.

Being on Fire - Fire does 4 damage per round + the Degrees of Failure on the agility test to put it out. If a character chooses not to make an agility test to put out the fire (or is unable to make the test at all), they count as having rolled a 100. An alternative is to simply use Degrees of Failure, if you feel that this is too punishing to characters with mediocre agility or willpower.

Toxic - Instead of a d10, Toxic does 4 damage + 1 damage per degree of failure on the test to resist it. If you would prefer a more set damage, I think that 4 + the toxic rating is a decent alternative.

Force - Similarly to Accurate, each Degree of Success on the Focus Power test increases the multiplier rating by 1. Also, like accurate, this is somewhat less powerful than the base game, but the same modification of +4 damage per DoS should undo that if desired.

Maximal - Instead of adding a d10 to damage, increase the base damage by 4 and the multiplier rating by 1.

Overheats - Use Degrees of Failure for determining the damage to the arm.

Primitive - Weapons with this primitive X cannot benefit from more than X Degrees of Success on the Attack. As an example, a bow (primitive 6) could never do more than 10 damage (4 base + limit of 6 DoS). I'd also personally suggest lowering the primitive rating of all weapons that have it by 1 or 2 to reflect this change in function.

Proven (x) - Weapons with proven x count Degrees of Success as x if they would otherwise be lower for the purposes of damage.

Spray - Since the attacker does not make any attack roll on Spray weapons, they use the Degrees of Failure on the agility test to avoid the attack in place of the non-existent Degrees of Success.

Tearing - Tearing weapons may use any pen leftover after armor reduction to reduce unnatural toughness (but not normal toughness bonus or the bonus from daemonic). 

Vengeful (x) - Weapons with Vengeful (x) generate righteous fury on any roll where the 1s digit is equal to or greater than x (e.g. a weapon with vengeful 8 would generate righteous fury on any roll that ends in 8 or 9, such as 38 or 29)

Multiple Hits and Righteous Fury - If you generate righteous fury on an attack that also generates multiple hits (such as full-auto attack), you only generate one Righteous Fury roll by default, on the first hit. However, you can decrease the number of hits you deal by one to get an additional righteous fury roll, as long as that would not result in rolling more righteous fury rolls than total hits. For example, if you rolled righteous fury on an attack that would result in 5 hits, you could choose to get 5 hits and 1 righteous fury roll, 4 hits and 2 righteous fury rolls, or 3 hits and 3 righteous fury rolls, but could not choose to get 2 hits and 4 righteous fury rolls.

Multiple Hit Damage(optional) - If you feel that the damage increase from multiple Degrees of Success combined with the fact that increased DoS mean more hits are overly strong, you can choose to make each Degree of Success either increase damage by one OR grant another hit. For example, if a base damage 8 weapon gets 4 DoS on a full-auto attack, you could choose 4 hits of 8 damage, 3 hits of 9 damage, 2 hits of 10 damage, etc. If the hit results in righteous fury, you have three choices on where to spend DoS - hits, damage, or righteous fury rolls. This is a pretty specific scenario for an already extremely specific mod, but I thought I might as well include it.  

Final Thoughts

These changes have a few major effects - low level weapons are far less likely to wound very high durability targets such as space marines and vehicles, high level weapons are very rarely going to fail to wound more vulnerable targets, like gangers and PCs; in short, damage is going to be much more in the middle.

Whether this is a good thing is mostly a matter of taste, but I think it makes for a fun change of pace from the d10 damage system.

(Editor's note: this mainly changes how damage is done, weapon qualities, and righteous fury. If a change not mentioned, follow the rules of the core rulebook for multiple hits, calculating DoS, and so on.)