This is my character, Sucky. I deliberately did not spend any stat points on character creation.
I went to the tavern and hired another character, Tagalong, with equally distributed stats:
Apart from stat distibution (gender, name, portrait and voice set), these characters are identical. So what do these additional stats give to Tagalong, and how much of a difference do they make, compared to levelling up?
Sucky at Level 1:
Tagalong at level 1:
Sucky at level 5:
SIGNIFICANCE OF INDIVIDUAL STATS
CONSTITUTION
Health and stamina bonus gives +9 both at level 1, while levelling up gave sucky +68 H/S (+17 on average), landing him a total of 119. As these values are percentage-scaled, according to my crude calculations, Tagalong would have around 141 H/S at level 5 (+20 per level up, 3 more than Sucky).
Note that characters in PoE basically 'start' at third level, which means they more or less double in power at level 4, and then at level 10.
So basically you have to put 10 points into CON to get around 3 H/S more per level.
In comparison, in D&D 3.5 you get 3 HP more per level if you up a stat by 6 points, but D&D damage scale is much lower overall.
For example, in D&D a light weapon deals 1-6 damage and a medium weapon deals 1-8. In PoE, a light weapon (hatchet) deals 10-16, while a medium weapon (battle axe) 13-21.
At low levels, higher CON will not even give you one level advantage, around level 5 it gives more than one level advantage, and this will only get higher further on.
Level 1: Sucky 51 Tagalong: ~60
Level 2: Sucky 68 Tagalong: ~80
Level 3: Sucky 85 Tagalong: ~100
Level 4: Sucky 102 Tagalong: ~121
Level 5: Sucky 119 Tagalong: ~141
Level 6: Sucky 136 Tagalong: ~161
Level 7: Sucky 153 Tagalong: ~182
Level 8: Sucky 170 Tagalong: ~202
Level 9: Sucky 187 Tagalong: ~222
Level 10: Sucky 204 Tagalong: ~243
In D&D 3.5 scaling of CON depended on your class. It could as much as double your initial HP (for mages) and since HP per level were partially randomized, it also had a larger impact during character development.
DEXTERITY
Dexterity to Accuracy is a flat bonus, so Tagalong has +9 ACC, because has has 9 more DEX.
Sucky got +3 ACC per level on average, so this is a flat advantage of three levels.
Accuracy significance is not very intuitive to grasp, but basically it operates on 1-100 scale, If I recall correctly, there is a random roll which like this:
1-10 miss (no damage)
11-50 graze (50% damage)
51-90 hit (100% damage)
91-100 hit (150% damage)
Your Accuracy is added to the roll, while enemy's defense (e.g. Deflection) is subtracted from it. In the broadest possible stroke +9 Accuracy is a +9% chance to increase your damage by 50% of your base damage (so +4.5% damage on average)
In comparison, +9 Might gives you a flat +18% damage. So yeah, like
Sensuki said, Dexterity kind of sucks overall. Even though increasing it by 3 gives you a whole one level up advantage, that still does not mean a lot.
In D&D 3.5 increasing Dexterity by 2 gave you a +1 to hit (with ranged weapons), which meant at least one whole level up advantage - or more for non-combat classes, but to-hit checks worked very differently there and it is hard to make a direct comparison.
INTELLECT
Increasing INT by 10 gives you a +50% effect duration and AoE. The usability depends on abilities used. I can easily see the effect duration bonus being useful - extending mind control (Puppet Master ability) from 34.5 seconds to 46.5 seconds has a large impact.
AoE range increase is useful in some cases. Many abilities have good enough range with minimal INT, but some will benefit from increased range (like Priest's Restore Stamina spells).
Increasing INT
is the only way to increase AoE and range of abilities.
They do not scale with character level.
MIGHT
Might increases ALL damage and healing numbers. I can see it as very important for priests and damage dealers and as a possible dump stat for support/crowd control focused characters.
Might damage bonus is more visible in higher-damage weapons and abilities, but you want as much bonus as possible for low damage weapons too, because of DT mechanic.
Base damage 10 vs DT 5 = 5 damage.
With 30% bonus from Might
Base damage 13 vs DT 5 = 8 damage (60% increase).
Weapon damage comparison:
Ability damage comparison:
As with Intellect, increasing Might is the only way to increase weapon/ability damage (and healing), as these do not scale with level.
PERCEPTION
Hard to say how useful Interrupt is, but I would boost Perception for fast-attacking characters, who land a lot of hits, because it is almost useless for hard-but-slow-hitting strikers.
Interrupt does not scale with level AFAIK, so you only have as much as you get from Perception.
RESOLVE
I have no idea if Concentration is any useful. It seems logical that it is more useful for characters using abilities with longer casting time (higher-level abilities?) but I do not se how these can be identified outside trial-and-error.
Concentration also does not scale with level.
IMPACT OF MAIN ATTRIBUTES ON DEFENSE
This is a separate topic, because various forms of defense are based on all character's stats, grouped into three pairs.
Pillars of Eternity wiki said:
Fortitude (FOR): Represents a character's endurance to "body system attacks" such as poison or disease. It is based on Might and Constitution.
Reflex (REF): Represents a character's ability to dodge area of effect attacks. It is based on Dexterity and Perception.
Will : Represents a character's strength of mind and resistance to mental attack. It is based on Intellect and Resolve.
There is also Deflection (AC equivalent), which is probably the most important of all defensive stats, but
attributes do not affect it in any way.
The other three are basically D&D saving throws copied to PoE and rescaled (so they use the same scale as Deflection). They all oppose enemy ACCURACY.
Starting Defense stats are based on your class (only).
Every point you put into an attribute gives you a 1.5 points defence bonus in the defense stat.
Additionally comparison, all Defense stats get a +3 bonus on each level up.
As you can see in the screenshots, Lv. 1 Tagalong has significantly better Defense atributes than both Lv. 1 Sucky and Lv. 5 Sucky.
Sucky gained 4 levels, so his Defense stats were increased by 36 points overall. You get as much Defense from assigning 24 attibute points. Tagalong has 57 attribute points advantage over Sucky, meaning he will only catch up to her LV. 1 Defense around 10th level.
2 attribute points in relevant stats are worth one level up when it comes to Defense. This is a lot of value, which means
Defense is the most important secondary stat affected by the main attibutes.
CONCLUSION
Based how often you Defense stats other than Deflection (I will call them saving throws below) are used, there are two conclusions.
1. If saving throws are often used, you can only safely dump one of the paired stats, or your corresponding saving throw will suffer. Basically, do not dump both CON and MIG, DEX and PER or INT and RES.
2. If saving throws are seldom used, I can only see MIG and INT as significant stats (with both being dumpable under certain circumstances), with the rest having very little impact on gameplay. Although with the number of points you get, you can easily max out these two and still have a decent number of points to divide among the rest.
