i have a a question...

[lain5246]

Okay, so in game there is armor class, damage reduction, dodge, and physical resistance rating. i would like to know if my interpretation of them is close to what the developers see them as. Armor class is like real combat experience, giving the chance to parry/avoid damage. damage reduction is the ability to straight up ignore damage. dodge is like instinct to move out of the way of an atk. finally we have physical resistance rating that reflects the resilience of the char. to bring that together a fighter has high armor class and physical resistance rating from armor and constant battle field experience, but low damage reduction acquired/limited limited by gear and dodge because of the heavy armor and shield. where as a monk has high ac and dodge to reflect their knowledge of fighting and ability to avoid being hit, but their physical resistance rating and DR are going to be significantly restricted because of their armor limitations. Barbarians use physical resistance rating, dodge, and damage reduction to reflect their rage state, but have low armor class to reflect their lack of care when getting hit. a wizard inherently has no real defenses so they use magic to get them. rouges and rangers are middle of the road getting some of all but not high tier in any. Is this on the right track?

[Selvera]

Well I can't say much about the systems in the game, I do know a fair amount about PnP, which this game was origeonally built off of.

AC -> This is an abstact number which determines the ability of your Armour to deflect blows, aka reducing the number of blows that actually deal any damage. The main sources of gaining AC are Armour, Shields, and Dexterity/Dodge.
DR -> This is the innate toughness of an object/creature that cannot be overcome in any way (no weak points), except to power through it. DR is common on objects (tables/chairs/doors) and specific monsters that are rather object-like (Earth Elementals, animated objects), and also on monsters that are supposed to have some sort of weakness will have DR, bypassed by their weakness, (Werewolves, Zombies/Skeletons)

Dodge, Prr/Mrr -> These do not exist in PnP. The dodge feat gives +1 AC.

There are also a number of discussions about house rules in PnP about using DR instead of AC, as it seems more realistic for what the system is trying to achieve (Why is the guy in full plate taking full damage from every attack while the girl in a dress gets hit more often?). Generally these discussions usually end with "It makes more sense flavor-wise, but it is hard to implement in a way that's balanced, so let's not bother."

[Khatzhas]

Okay, so in game there is armor class, damage reduction, dodge, and physical resistance rating. i would like to know if my interpretation of them is close to what the developers see them as. Armor class is like real combat experience, giving the chance to parry/avoid damage. damage reduction is the ability to straight up ignore damage. dodge is like instinct to move out of the way of an atk. finally we have physical resistance rating that reflects the resilience of the char. to bring that together a fighter has high armor class and physical resistance rating from armor and constant battle field experience, but low damage reduction acquired/limited limited by gear and dodge because of the heavy armor and shield. where as a monk has high ac and dodge to reflect their knowledge of fighting and ability to avoid being hit, but their physical resistance rating and DR are going to be significantly restricted because of their armor limitations. Barbarians use physical resistance rating, dodge, and damage reduction to reflect their rage state, but have low armor class to reflect their lack of care when getting hit. a wizard inherently has no real defenses so they use magic to get them. rouges and rangers are middle of the road getting some of all but not high tier in any. Is this on the right track?

DDO has moved a way away from PnP, and some of these systems have a certain amount of overlap with each other.

Armour class is the base chance of landing a damaging hit on your target. It takes into account an evasive target avoiding your blow (Dex mod) as well as your strike connecting, but dealing no significant damage because its impact was absorbed/deflected by the target's armour. Combat experience doesn't really enter into this, although magical effects that replicate armour or evasiveness do. (Deflection, insight etc modifiers to AC.)

Damage reduction is the ability to just plain ignore minor damage. Barbarians can ignore some of the damage and pain from being hit, minor wounds simply being shrugged off completely. Other creatures might need a magical weapon to penetrate their DR for example, so a mundane blow will be severely reduced or even ignored completely. This might represent the inherent toughness of the creature's composition or the wounds regenerating instantly etc.

Dodge is, as you say, the ability to move out of the way of an attack that might otherwise hit you.

PRR is a straight reduction in the damage being dealt, generally due to a character's worn armour and experience in using it. Even if a strike does deal damage past the armour, its impact is still reduced.

The reason that PRR and Dodge exist is mostly due to the power level in DDO. AC broke down since the mobs had such huge bonuses to hit, so other ways of defence had to be introduced. (Otherwise you had the situation that casters were far tougher than heavy-armour wearing warriors etc.) Hence why PRR and Dodge seem to replicate parts of the original AC system.

[Qezuzu]

PRR is the equivalent of PnP's damage reduction, except since it's proportionate to damage, they can continue increasing mob damage in new content but still have their system of damage reduction be relevant, since it's not additive (like how regular DR is not relevant i.e. Stoneskin's DR 10/- is incredibly useless). Though, I don't believe DR was ever supposed to reduce damage by as much as 70%...

Dodge is to AC in the same way, it will work no matter how high mob attack goes. Indeed, dodge bonus used to simply be a bonus to AC.

They're just put in place so we can continue increasing the power level of the game to ridiculous levels.

[Ligraph]

Best way to find out is to read the wiki.

PRR

MRR

AC

DR

Dodge (pay attention to max dodge and max dex bonus!)

For the AC forumla on the wiki, a monster's to-hit is 2.5 times it's CR, as far as I can tell (using the "defense chance at level" info).