Round 2 of this damage calculation stuff... I started with a few hypothesis and then included the proof (+) or contradictions (-).
1) Each hit increases the normal damage portion, but not the elemental damage.
+ Explains the lower % bonus of later hits
- Even if the elemental damage did nothing to resistant creatures, their percent should drop each hit but instead it is steady.
2) Pure damage weapons are not pure
+ Flourish appears to have a similar bonus as a split damage type like DA/Acheron
- Flourish has double the penalty compared to a DA/Acheron
Examining these two, led me to believe that the calculations for weakness and resistance cannot be the same.
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So to test Hypothesis 1, I started with DA at Depth 22. There are many unknown variables and too few formulas to determine their values. So I started with the guess that Hit 1 is half normal and half elemental damage. This would mean that the Elemental Bonus would be calculated as follows:
E = N = 115.5
E*Ebonus + N = 251
Ebonus = 1.49351
Then checking the Hit 2 and Charge attacks, I found them to match up perfectly:
......D...E.....N.....Calculated Damage for Weak
Hit 1 288 115.5 115.5 288
Hit 2 368 115.5 195.5 368
Chrge 554 115.5 381.5 554
Calculated damage is E * Ebonus + N.
How about that. The numbers match up exactly. Repeating the process for Depth 19 with an elemental bonus of 1.48913 had results within 0.2%. Depth 24 and 28 have Ebonus values of 1.58091 and 1.80342 with calculations withing 13%. I think that the defenses of creatures in Strata 6 is not perfectly linear as they are in other strata, which makes the calculations deviate from normal. But the results are still close enough to show that the elemental portion of attacks does not change.
So Hypothesis 1 might be true. Only the first hit of a split damage weapon does half elemental damage. After that, only the normal portion increases whereas the elemental portion remains the same.
One problem though - this isn't true at all for creatures that are resistant to elemental. The normal portion of damage in the second hit is already higher than the resulting damage. I think that the calculation for them is just a straight Total Damage * ~60% (aka 40% penalty).
So why bother? Well, if the DA's charge attack was 1/2 elemental and 1/2 normal then the hit would do 620 instead of 554 damage vs weak at D22. Maybe that was way too high, so subsequent hits are nerfed by not increasing the special damage component of the weapon along with normal. Or maybe it is a bug.
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Hypothesis 2 - pure special damage weapons (i.e. Flourish) are not pure. I couldn't think this one could possibly be true, I had to be missing something. Especially since there is a whopping 80% damage reduction due to an automatic calculation for pure damage against resistant creatures.
Depth 22 Piercing Bonus = 1.62222
......D...P..N...Calculated Damage for Weak
Hit 1 236 90 90. 236
Hit 3 282 90 134 280
Chrge 384 90 237 383
Calculated damage is P * Pbonus + N.
Yep. The Flourish vs Weak is actually 1/2 normal and 1/2 piercing for the first hit, Also, like the DA, the piercing damage doesn't increase for subsequent hits only the normal damage component.
These numbers check out for D19, D24 and D28 too, all within 1-6%.
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Thoughts? Other possible explanations for the phenomena?
Thanks for doing this. These tables definitely help and can be applied to other things like the slow vs. med sword debate, especially when you add in UV's.
I'm also confused about the diminished return on the final blow of the weapons, since there is an inherent risk of finishing your combo sometimes (cf with 2hit-shield cancel on a medium sword). My initial thought was that it was a balance issue, where the devs probably didn't want to 2-hit everything to death, but a quick test on a random zombie on d19 proved otherwise, with HP's that exceeded 2 hits, and sometimes even the 3 hit. As to the flourish, I think it's kind've weird too, considering the huge penalty associated with it.
And for what it's worth, a glacius is equivalent to an acheron in terms of absolute damage (ie. I was getting the same numbers).