Minor Aegis inconsistent mitigation

superryan94

I was looking a bit into damage mitigation for a little project and noticed that the damage reduction from Minor Aegis is a bit inconsistent.

In order to test this properly I needed to eliminate any form of influence from external sources of mitigation. So my base was as follows:
0 CP slotted. This was to make sure that CP does not add any form of extra mitigation.
3 heavy armor pieces. This is to enable or disable Minor Aegis. I equip a golden CP160 yolnahkriin's cuirass, gauntlets and depending on whether I want to turn on of off Minor Aegis, a yolnakriin's girdle of no setpiece rubedite girdle, all with the sturdy trait and a golden cp160 health enchant. By switching out the waist I do not change any stats or remove/add buffs except the Minor Aegis.
I slot golden CP160 adept rider's jewels in protective trait to boost my resistance a bit and use balance to up it even more. I did this because they give no other buffs to damage(according to the tooltip) and less than 5.5K resistance was not really a good test in my opinion.

Now I need a damage source which is sure to do a lot of damage.
Olms in vAS is a good place. He hits for 155478 base (and with all light armor up to 167121 ). Plenty of damage to work with.

Next I needed to test the damage on different levels or resistance.
Because the armor penalties and bonus things can influence results I need to use medium armor as this neither increasen nor decreases damage taken.
I equiped white level1 helmet, shoulders, legs and boots.

Everything setup, I let myself get slapped by olms with and without Minor Aegis equipped.
The damage I took as baseline(armor buff already included) was 51561 and with Minor Aegis was 49190. The mitigation Minor Aegis gave me here was 4.82%.

Rinse and repeat each time either helmet or shoulders 1 craftable level up, and this were the results:


Okay, so the mitigation is ~4.82%, not the 5% the tooltip claims.
But in a few other runs I did I got 5.001% and 4.598% which is quite the deviation, especially downward.

What makes it go up or down from the value tooltip states?

PS: if I did something wrong in the testing, please let me know and I'll redo it and see if that solves the inconsistency.

tsaescishoeshiner

What this reveals is that the "reduced martial damage taken" heavy armor passive is multiplicative with other unspecified "reduced damage taken" buffs. It's expected to work this way with armor, but I didn't know it worked that way with other kinds of reductions.

That 51,561 isn't Olms' base damage, it's reduced by your armor and by your heavy armor passive. So for comparing Minor Protection, it's not 100%, it's more like 97%.

Mafs:
95% * 97% = 92.15%
92.15% – 97% = -0.0485

So there's 4.85%, which is much closer to what you were finding. 4.82% would make sense if you were at 96.4% reduced damage before Minor Protection. Where those extra percentage points are coming from, I'm not sure.

This old forum thread is a good reference, but of course details of it are liable to be out of date, and it used to be edited for unmentioned changes, which happen sometimes: https://forums.elderscrollsonline.com/en/discussion/279426/damage-mitigation-explanation-updated-15-07-2019/p1

superryan94

Well, I did mention that olms hit for 155478. The base you refer to is the damage I get in 3 heavy, 4 medium blocking the attack. This already does have the 3% armor buff in it in both cases.

superryan94

Not saying it's a bat formula. It's a really good approximation and the work that was needed to get that close is a lot.

But some of the parts in that formula are not completely correct.
For example, resistance does not count until above 100 and going from 32999 to 33000 gives the same resistance increase as 200 point elsewhere.

Because of this, the "resistance mitigation=resistance/660" is not completely true.

I'm currently trying to get something closer, but that takes weeks if not a few months to figure out.