Detailed combat mechanics?

Thanks for all the feedback, esp. Mark.
But i am now somehow confused about the difference of "Attack" and "Spell":
I understand, that a 'basic attack' (no skill) is an attack, and i understand that this attack can include elemental damage, which will be reduced by resistance, not armour.
I guess now, that Melee/Ranged Skills (like Glacial Hammer, Lightning Arrow) is still an ATTACK, whereas a ranged spell skill (like Fireball) counts as spell. Correct?

I am asking primarily because of the difference of Acrobatics and Phase Acrobatics.
So, Acrobatics add a flat 20% dodge for all attacks if the attack would hit (so no evasion), right?
So a perfect "evade/dodge char" would have a mitigation of attacks by 95%+5%*20%=96%.
For an average evasion character (50%), Acrobatics would "increase" the mitigation to 50%+50%*20%=60% (so 10% "bonus").
Conclusion: Acrobatics makes more sense for low evasion characters.
Looking at the backdraft (losing all armour and enery shield) does "relativate" this leaving only block as additional form of damage mitigation.
Phase Acrobatics introduces a flat 20% spell dodge, which is alway 20% since spells cannot be evaded/blocked. So 80% of spells hit, but the damage is reduced by armour for physical damage components (but armour is 0 due to Acrobatics....), elemental damage reduced by the resistances.

So just some number crunching:
Case Study I:
Defenses:
Armour 50%
All resistances 50%
Evasion 20%
Block 30%
Energy Shield capacity 500

Attack:
100 damage physical, each element, no chaos damage; attacker has 95% hit.
The attacker will hit with 0.95*0.8=0.76=> 76% chance.
If he hits, block is calculated, so hit will still occur with 0.76*0.7=0.532=>53.2%
Physical damage as well as each element is reduced by 50%, leaving 50 damage per 'damage source'. So damage cought by the energy shield is 4 (fire, lightning, cold, physical) * 50 = 200 damage, leaving the energy shield by 300 points.
So the overall mitigation for infinity number of such attacks would be:
0.532 (chance to get damage at all) * 0.5 (resulting damage because of resistances) = 0.266=>26.6%

Case Study II:
Defenses:
Armour 0% (Acrobatics!)
All resistances 50%
Evasion 20%
Block 30%
Energy Shield capacity 0 (Acrobatics!)

Attack:
100 damage physical, each element, no chaos damage; attacker has 95% hit.
Again, the general hit chance is 76%. But instead of blockcheck, Acrobatics "jump" in. So the hit chance for the block step drops to 0.76*0.8 = 0.608 => 60.8%
Now blocking: 0.608*0.7 = 0.4256 => 42.56% to hit. This is 10.64% less chance to hit for the attacker in comparison to the previous case study.
Now to damage. Physical damage is reduced by 0 (backdraft of Acrobatics), whereas each elemental damage is still reduced by 50%. Damage total therefore: 250 (100+3*50).
Since we got no energy shield (second backdraft of Acrobatics), the damage is dealt to the life pool directly.
Overall mitigation for attack damage would be 0.4256*(250/400)=0.4256*0.625=0.266. Also 26.6%, just as Case I.

Conclusion I:
If both attacks would include 100 chaos damage as well, Case I would lose 200 energy shield and 100 life, Case II would lose 350 life.

So Acrobatics makes sense for low armour, low energy, high HP characters! But looking into the passive tree, i somehow fail to realize where a high HP pool should derive from (Acrobatics being a more or less "pure" Dex skill!). It makes sense though, that increasing energy shield nodes are not in range.

So, thinking about it, Acrobatics has its appeal, even with its severe backdraft, but i somehow feel that the tree needs some little rework for the surrounding nodes (putting in some decent HP increasing nodes).

Well, just some number crunching....

Nordstern

Case Study III:
Damage with chaos component.
A) Values as Case Study I, but 100 chaos damage.
With 53.2%, the damage will take place. The damage will be 200 against the energy shield/HP pool, 100 (0 chaos resistance) will be against the HP pool. The damage totals up to 300 damage (of 500 possible), one part being possibly mitigated by the shield pool (well, HOW do we calculate that into some %???). So lets deal against the HP pool only:
0.532*(300/500)=0.532*0.6=0.3192=>31.92%

B) Values as Case Study II, but with 100 chaos damage.
0.4256*(350/500)=0.4256*0.7=29.792%
So chaos damage has less "effect" in such damage combinations since the chance being it is less.

Case Study IV:
Defenses
Armour 65%
All resistances 70%
Evasion 12%
Block 40%
(Note: i think this could be reasonable for e.g. Templar)
No energy shield (since THIS is a mitigation component which is very strong, esp. if cooldown recovery is trained. It is hard to calculated here, since it would be a race between recovery cooldown reduction/increased recovery against attack speed)

Attack
Again 100 Damage everything, including chaos.
Hit again 95%.
095*0.88=0.836 to hit before block.
0.836*0.6=0.5016 to hit after block. 50.16% hit ratio.
Damage dealt:
100*0.35+300*0.3+100=225 Damage

Overall damage reduction:
0.5016*(225/500)=0.5016*0.45=0.22572=>22.572%

Case Study V:
Defenses
Armour 0 (Acrobatics)
All resistances 30%
Evasion 60%
Block 0 (Lets say we got a bow)

Attack
Again 100 Damage everything, including chaos.
Hit again 95%.
0.95*0.4=0.38 before dodge.
0.38*0.8=0.304 after dodge. 30.4% hit ratio.
Damage dealt:
100+300*0.7+100=410 Damage

Overall damage reduction:
0.304*(410/500)=0.304*0.82=0.24928=>24.928%.
This is less than Case IV, but maybe my numbers are not being picked "properly". So let's look, how high Resistances/Evasion has to be to match Case IV:
0.22572/0.304=0.7425.
So overall damage dealt must be 74.25%, not 80%. Reduction must be 25.75% instead of 20%.
For such an evenly distributed damage package, we could use e.g. keep 60% Evasion (looks realistic, no?), so elemental damage has to be reduced to 0.7425*500-200=371.25-200=171.75 damage (the 200 are 100 physical "no armour" and 100 chaos!).
For an initial value of 300 elemental damage, this means 1-171.75/300=1-0.5708=>42.75% average resistances. Does this look realistic?
This would mean, resistances has to be increased by over 13% in comparison to Case IV.

And again: The evasion player has to keep a higher HP pool since he has the higher damage hits, but they occur less often! Another thing is that he omits energy shield which i find very strong.

My personal conclusion from those Case Studies is:
- Acrobatics is not meant for tanky charcters.
- Acrobatics makes only sense if walking down the complete path in the skill tree and get Phase Acrobatics. The skill between raise dodge to 24%, which would alter Case V to:
0.38*0.76=0.2888 hit ratio after dodge
Damage dealt still 410 (taking numbers of Case V unmodified)

Overall Damage reduction:
0.2888*(410/500)=0.23682
So resistances should be upped to about 36.5% to match Case IV (6.5% increase for resistances). This is huge difference to Case V, where the resistances have to be increased by about 13%!

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Mark_GGG wrote:

Spells are not attacks, attacks are not spells.

This is going to sound really silly, but are traps and mines spells? This question is regarding both, pre-built traps/mines (fire traps, bear traps, freeze mine, etc), and those made through support gems. =S

Thanks!

"

ac429 wrote:

"

Mark_GGG wrote:

Spells are not attacks, attacks are not spells.

This is going to sound really silly, but are traps and mines spells? This question is regarding both, pre-built traps/mines (fire traps, bear traps, freeze mine, etc), and those made through support gems. =S

Thanks!

I'm not 100% sure but i think that they are not spells. They are affecte by general e.g. +fire damage and by special trap passives (obviously)

Nice thread this was exactly what I was looking for !
Although I skipped the part about special skills such as phase acrobatics or whatever the blocking mechanics is really important.
Thanks for all the great answers