I’ve heard a lot of people complain about the implementation of Damage Resistance/Damage Reduction in Borderlands, and specifically, a lot of complaints about how Damage Resistance is subject to diminishing returns. I wanted to take this time to dispel that rumor, as it is quite untrue. First, let us define diminishing returns:
“[A]ny rate of profit, production, benefits, etc., that beyond a certain point fails to increase proportionately with added investment, effort, or skill.” (http://dictionary.reference.com/browse/diminishing-returns)
The following is the formula by which incoming damage is calculated in Borderlands 2 and Borderlands The Pre-Sequel:
Damagefinal = Damageinitial / (1 + Resistance)
As you can see, incoming damage is divided by the sum of all damage resistance acting on the player, plus 1. If for example one was specced 5/5 into Claptrap’s skill Pain Simulator is Painful, all incoming damage would be reduced by ~17% (100/1.2=83.33). Now, for a lot of people this immediately seems suspect; I have 20% damage resistance, so how come I’m only shaving off 17% of damage taken? Many would assume that because the final number is lower, diminishing returns are reducing the contribution of damage resistance. As an even more dramatic contrast, at 100% damage resistance the actual damage reduction comes out to a mere 50%.
This is not diminishing returns at work. Point-for-point, damage resistance offers the exact same defensive benefit no matter how much damage resistance you have. A more intuitive way to think of damage resistance, is that it increases your effective health by 1% per 1% damage resistance. As an example:
Let’s say you have a health pool of 1000. A bandit pulls out a shotgun and shoots you, dealing exactly 1000 damage (We will ignore health gating so as not to confuse anyone). Now we’ll add 100% damage resistance; at 50% damage reduction, you now take 500 damage from the shot. You have effectively doubled your health pool. Where before you would have went down from exactly 1 shot, you can now take 2.
Same scenario, but with 200% damage resistance; at 66.6% damage reduction, you take 333 damage from the shot. You have effectively tripled your health. And so on, and so forth. No matter how much damage resistance you acquire, it always has the exact contribution of 1% effective health per 1% damage resistance.
I suspect the reason for the confusion is the misleading name that is damage resistance. I personally have always taken damage resistance/reduction to mean 1% less incoming damage per 1% damage reduction. I feel that Gearbox should rename damage resistance going forward, to something that has fewer preconceived notions about it. If nothing else, it would be nice if they stuck with either damage resistance or reduction, as that inconsistency can only serve to add to the confusion. Also of note, the issue is compounded by skills like Jack’s Delegation, which do work in the aforementioned fashion (citation needed). For anyone with a mind for game balance, it should be pretty obvious why implementing readily accessible damage reduction in Borderlands would be tricky. If they allowed it to stack additively, players could potentially find a gear/skill combo that puts them at 100%, which would wreck end-game encounter design. Gearbox would need to either heavily restrict potential sources of damage reduction, or implement a hard cap on how much DR players can stack.