Introduction With the advent of level 90 epics, there’s a modifier on certain items called “ignores percent defense.” This has since spawned far too much incorrect information on how enemy defense works. In this thread I’ll be talking about both flat defense shred and percent defense shred, showing in the process why supports are so highly rated in the current endgame content that is Anton Raid. I. The Defense Formula and Flat Defense Shreds From Rhaevan’s excellent informational thread (http://www.dfonexus.com/threads/damage-defense-and-criticals-the-damage-formula.304/), we can find that the defense formula is: Percent Reduction = D / (D+200L) D= Numerical Defense L= Attacker’s Level This does not appear to be 100 percent accurate throughout all my testing in training room vs Ex Nugol, but the error is within 5%. If we graph this formula we see the following: This is taken from 0-250k defense at 10k defense intervals. Note that, based off testing on the reinforcement machine, enemy defenses cannot be lowered below 0. What we can see is that flat shreds actually have increasing returns; that is, each additional 10k defense shredded adds more damage. It’s easier to see in chart form: The important column here is Column E, where you can see the relative damage gained from each additional 10k defense shredded. Getting as close to the 100k defense shred cap in Anton Raid is thus an extremely powerful way of increasing your group’s damage. II. Percentage Defense Shreds In the future, we move towards percentage defense shreds. I can’t make a graph I’m happy with to show the effects here, so instead I’ll show a single case. Bremen at level 30 and 6 Unholy Dominion in the latest KDnf patch reduces enemy defense by 40 percent. Here’s how it looks: From column G, we see that Percentage defense shreds have diminishing returns with respect to enemy defense. This may seem incorrect given that I just said numerical shreds have increasing returns, but think about it like this- When an enemy has 200k defense, a 50% damage shred will remove 100k defense. When an enemy has 20k defense, it only removes 10k defense. This vast difference in defense removed results in the diminishing returns you see in column G. This is not to say you shouldn’t stack as much percent defense shred as possible! Adding more sources will have increasing gains, as shown in the Flat Defense Shred table. III. Multiple sources of shred: How they Interact If your party has multiple defense reductions, they interact thusly: a) The game will first calculate flat defense shred, and then percentage shred. For example, if you have Bremen (76k flat) and Asura’s Thunder God Energy (18.5%), then Bremen will apply first, followed by Asura’s Thunder God Energy. b) If you have multiple percentage defense reductions, they are additive. For example, Knight’s disarm (12%) will add directly to Asura’s Thunder God Energy (18.5%) to give 30.5% defense reduction total. This order of operations makes percent shreds a little weaker. Recall again there is a 100k defense shred cap in Anton Raid, so you'll never be able to remove 100% defense. IV. Ignores Percent Defense Disclaimer: nobody knows how this works yet. Everything here is theory only. With that said, I can see 3 main ways this will work, taking the assumption your weapon has a 25% ignore and also have a 40% defense shred through Bremen available. 1) If a larger percent shred like Bremen exists, then the modifier will not work at all. You attack into 60% of a monster’s initial defense value. 2) If a larger percent shred like Bremen exists, then the modifier will apply multiplicatively. The enemy has 60% effective defense, of which you ignore 25% of it. You attack into 45% of a monster’s initial defense value. 3) If a larger percent shred like Bremen exists, then the modifier will apply additively. You attack into 35% of a monster’s initial defense value. This is listed in increasing order of power. Again, I must re-iterate that nobody knows how this works yet, so these speculations could easily be entirely wrong- but it should give an idea how powerful this mod may or may not be. V. Piercing Attack Any and all defense shreds have no effect on your damage caused by piercing from reinforced weapons. Piercing damage ignores enemy defense, but can get modified by enemies having piercing damage reduction. Conclusions The important takeaway here is that flat defense shreds have increasing returns. This is why Iron strike and Bremen are so potent in our current meta. Taking Bremen for example, using an average value of 150k defense in Anton Raid, shredding 76k defense with a 30/6/6 setup gives ~65% more damage to your dealer(s). If you can push to the 100k defense cap, then your dealer(s) gain ~100% more damage.