So, considering we'll soon invest in an attacking art, I thought it might be good to look into what defines a good attack skill. This is just some rough work into the system, so please point out any mistakes or bad assumptions I've made here.
First and foremost:
This is a simple calculator to see how likely we are to hit with a given dice pool. Feel free to change the number listed after ATTACKER: and DEFENDER: to change the number of dice the attacker and defender have respectively. In the results, the first number listed under 1 is our hit probability. The second table shows our chances of doing a certain amount of damage (you can change this to display exactly, at least or at most a certain amount of damage as well). You can use it for other things, but not everything has a defender, so ties aren't necessarily known. DAMAGEBONUS: assumes flat damaged gained from an art (e.g., Zephyr's Grace gives +1 damage).
I'll get back to this in a bit, but for now let's talk about the system.
DV is an odd thing. Consider, for example, what a DV 4, as we have on our knives, actually means. People are saying this is pretty low, but that's not necessarily the case.
To beat someone's defense roll by 4 with any degree of frequency, you need an absurd dice pool advantage.. If we were to fight a clone of ourselves in the dark, there's a
.31% chance that we'd inflict enough damage to run into DV without problems with arts. Using Guiding Zephyr, the chances rise to
5.46%. Of course we have no good combat arts to attack. If we had the 17 dice we pushed against the worm, that's a 1.73% chance of taking that much damage. Assuming we can debuff people to hell and back,
we still only run into the damage cap 10% of the time without adding arts.
Without looking into damage boosting arts, which we haven't really seen yet, DV won't really matter
too much as long as it's above 2. Now, arts might change this, or bypass DV entirely and simply add additional damage on top. With attack arts, it's harder to say. However, given that big weapons have DVs of, say, 10, which would need an absurd dice advantage to ever matter, it's probable that most big damage arts don't bypass DV.
Now, let's look at resources. 2 Qi can be traded for avoiding 1 damage. So, having 2 Qi in our pool gives us an effective 1 HP. This isn't perfect, effects may negate the ability to transfer normally, but in general, we can think of spending 2 Qi to do something as losing 1 HP. We can see though, that it's generally plainly a waste to spend 20 qi on an art to prevent 5 damage (absent other effects or unknown factors).
What about in practice with attack arts? Pretty simply, if the expected (e.g., factoring in hit chance) damage you gain from using an art is more than twice its qi cost, the art is good to use in a given turn.
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Let's put this together in practice. Take two equally skilled fighters, each with 11 dice to their basic pools for attack and defense (stat 6+mastery 5). The defender has armor that gives +1 to defense and the attacker gets +2 from weapons when using an appropriate element art. Both have roughly equal qi pools.
Now, the simplest attack art can probably be described as either "get very accurate" or "do a ton of damage on hit". It also gives, automatically, it's rating in dice to the attack. Let's say it's a 3 dot art. A comparable defense art is probably something like Crescent's Grace. We'll use these numbers (+3 for 3 turns, +6 the first of those, misc benefits, costs 5 qi) though a low level defense art might be a bit worse. Let's say both arts cost 5 qi. Let's say both get a 2 qi cost reduction on their arts, meaning both arts effectively cost 3 qi.
So, this gives us a few meaningful situations.
No arts: which is
11 to attack vs 12 to defend
Attack art vs no art, which is
16 to attack and 12 to defend
Attack art vs defense art which is
16 to attack and 18 to defend
Attack art vs defense art after the first round, which is
16 to attack and 15 to defend.
No art vs residual defense art, which is
11 to attack vs 15 to defend
Now, in all situations but the first defense art, the defender is resource neutral that turn. The attacker, we assume is paying to use the art every turn (longer duration effects presumably exist, but complicate dice pools enormously and we haven't seen many attack arts yet.) They're spending 3 qi, roughly 1.5 health.
Using no arts, the attacker has a 35% chance to hit, and a 20% chance of doing 2+ damage. CG costs 3 qi. As a back of the envelope calculation, defending against 2 damage would cost 4 qi. At 20%, that's probably .4*4=.8 qi. In this sense, it doesn't make sense to use CG to defend, since you can just soak the hit with qi more cheaply. It's a bit more expensive in practice, but overall pretty worthless to use arts. The effective swing on no resources spent against an enemy, is a .8 qi gain, roughly .4HP over them.
Using the attack art, the chances of hitting are now 66%. 2 damage comes in at 51% based on this dice pool. That's, again, 4 qi. 4 qi paid half the time is 2 qi lost. Note, the attacker is paying 3 qi every round, so the attacker is losing this fight. So, just based on the dice, it's not a gain to do this. Let's say the attack art adds a modest 2 damage on a hit. Well, now that's 4 damage or 8 qi half the time. It's 4 qi/round generally (again this is optimistic on defense, but easier to math). Here, we see a slight gain in spamming this attacking art. CG may be a gain for the defender.
That gives us our third situation. We're back to a 32% chance to hit. And the odds of doing 2(+2) damage are now at 21%. That's still 8 qi in HP. .2*8=2 (+3 from CG) equals to 5 qi per action. This means, using CG is still likely a loss if we're only considering the first round.
Looking at the later rounds...
Here we have a 16 v 15, that's a 48% chance of hitting and a 34% chance of doing 2+2 damage. .34*8=2.72 qi spent to absorb damage. It's plainly not worth it to pump up CG again. CG is saving (again, this is a very optimistic back of the envelop calculation for defense). The defender loses 1.3 less qi per round with this art, spending 10.2 qi over the duration of CG. Without using CG, we'd have spent 12 qi. So, CG is saving us 1.8 qi then over its duration? Right? No.
Quite simply, the attacker, seeing a buff, isn't going to spend on their attack art until they see it drop. This means they spend 3 qi to force us to spend 5. This gives them a negligable 20% chance to hit, and a 10% chance of making us take damage. That means they save 6 qi on their art usage and we take .4 qi loss/round. This means that spending on CG is 5.8 qi.
In short, using the attack art on the first round (realizing it's a short duration buff), they spend 3 qi and we lose 5.8-2.4=3.4 extra qi over them not using the art at all. In this sense, they force us to lose .4 qi relative to no arts being used. That's basically a wash with CG as far as I can tell. Note, a major use of the art is threatening. They use it to make us pop buffs, which in turn makes us bleed qi, not spamming it.
Note, comparatively, Elegy is sapping 2 Qi from everyone every round, likely with better dice pools in many cases. Note that the hypothetical attack art here, providing effects comparable to CG, (though CG does other things) would make an equal level opponent spend 3.4 qi over 3 rounds, 1.133333 per round. If Elegy is working consistently, it's significantly more powerful. If Elegy is hitting less than half the time, it's still pretty potent damage/round (note that we can make it one of our best dice-pools, while many may not max resolve until we get far further in cultivation and more and more stats tend to max out) with a wide AoE.
Note, that, again for DVs, an art that gains something like 2 damage on hit is already comparable, if not better, to the effects that CG gives on defense (again, I oversold the defense somewhat with these simplifications, the actual expected cost/round is worse). Going back to DVs, that means a DV of 10 is intense +2 damage is already enough to be a useful attacking art. Pragmatically, a DV of 5-6 is all we would ever realistically need unless attack arts tend to be dramatically more powerful than defense.
Does this look about right?
