Is accuracy rating (Perception + Dex) affecting spell hit chance?
I'm wondering if a mage build needs Perception and Dexterity to land spells more often. How about DD spells? And more importantly how about illusion, charming, psychic attacks, healing or bard skills?
For pure Intelligence based, targeted DD spells it might make sense. For psychic, charm and illusion spells (magic schools governed by Int + Charisma) it makes a lot less sense. For summoning or bard spells it makes no sense at all. And it would be a problem for making efficient charisma-based magic builds, as one would need Int + Cha + Perc + Dex to be efficient (with very little health as a result).
If Perception and Dex are the basis for hit rates (accuracy) of all types of attacks (melee, archery/ranged and magic), then marksmen and assassins would clearly have a huge advantage, as these are their school-governing attributes anyway. They could then easily stack health (Con) and mana (Int) on top, while the charming mage would have to live with minimum health and carrying capacity.
Finally a related question: is evasion (Dex) also affecting spells?
not saying you're right, or your wrong, but that there are finer points to be examined.
I'd say that all of those thing will matter, at least to some extent. having a character kitted out as a dodge tank being told "oh, by the way, you're entire concept is useless against bards and psychics" would be a bit unfortunate. I agree some spells ought to care less about evasion rates than others, but I also doubt the devs ever want to create a situation where having a poor stat isn't a big deal for one particular sort of character or build. (either have it a big deal for everyone, or no one, is fine - just, no special cases, if possible)
I will also say that, for the purposes of direct damage and effects, I doubt that you'd need both input stats to use it well, just because stats are so hardwired the way they are. if they were additive, then the basic Illusions spells tossed on a pair of 15's would overwhelm the damage output of any single stat spell at max caster strength (25). They can't be averaged, either, for similar reasons - making someone pay 60 points to be as effective as someone spending 30 is also bad design. I'm going to guess they'll use a formula like [The higher of the two stats] + [the lower/5 (rounded to the nearest integer)], using the same natural cap everyone else has on the result. make the secondary count some, but not so overwhelmingly that someone can't find another way to get to that cap, if they are really determined. In essence, I'm saying an Intelligence mage is going to be able to cast everything "well," even if they ignore the other stats, but that an illusionist can do just as well with Charisma, assuming reciprocal stats.
There are other concerns - like the fact that Illusions, all things being equal, will screw accuracy builds. okay, fine, you can hit my mirror clone, but it takes you three hits to kill one, and I've spawned 3 more in the meantime (spit balling here, but playing the shell game is a stand-by of illusion skills)
Further, the illusionist gets scaling damage on their illusions, something archers don't get from dex or perception. Sure, the archer can shift to casting...but, lets be honest, once you say that, why use a bow at all?
remember that spells don't home to a target. Although there might be a few that do, it'll be an exception. they fire in a direct line and whatever is in the way gets hit.
this allows tanks to be shields for their friends or allies.
@atoro Let's talk like this. The game has magical and physical abilities. With the improvement of a certain attribute, our accuracy grows. Attributes were divided into 2 types : for the magician and the melee player. From here we conclude that there are 2 accuracy indicators for physical and magical skills/attacks in the game. This figure allows us to fall on enemies (is logical, Yes?), but we take it to hit enemies with high evasion, as we want to cause damage.
Thanks for all the answers, gave me some new perspectives. They seem to be a bit contradictory, so it might all be more complex than expected.
If the higher skill (of perception or dex) has relatively more impact on accuracy (as @TheRipperOne suggests) it would be better to go 18 Perception for the extra accuracy bonus. If most spells do not depend on accuracy (as @Jetah suggests) a mage could skip Perception and take Dex 18 for the evasion bonus (or none of them, going for e.g. Con). Who knows, anything is a good guess at the moment.
There is no mention anywhere of a separate physical vs. magic accuracy, so I do not agree with @muker on that.
Charisma mages might be very strong against chars with charisma 6 (something many melee and archery chars will probably use), on that I do agree.
Still, Perception looks like an uber skill for every build, heavily influencing such important stats as accuracy, critical hit, gathering, identification of items etc. (+ assassination & marksman). In comparison Strength and Charisma are much more constricted to specific builds (melee, illusionist, bard or summoner). On the other hand, Int is also a must for basically any build.
this is why we're not theorycrafting right now. there are too many unknowns.