If you were to design your perfect RPG, would you implement an armor class/armor resistance or damage reduction rule?

What I like about AC (D&D) and AR (Palladium) is that you have a simple number to roll against to determine 1) did I hit and 2) did I hit well enough to do damage. There is something about rolling a d20, adding some numbers and then exclaiming I hit AC 18 (or 2 if old-school). I like this. I have a hard time articulating why but I like it.

What I enjoy about Damage Reduction (Armor Protection) is that even if you get hit, you pray/visualize/hope the opponent's damage is less than your DR. One variant of DR I prefer is random DR (ala Stormbringer 1st ed). There was something cool about rolling a d10+2 (Plate+Helm) against an opponent's Lormyrian Axe (2d6?). I did not enjoy straight DR (Runequest) quite as much.

So, any preferences out there? Armor makes you harder to hit or armor absorbs damage? What is cooler to you and why?

Thanks!

Eric

I like random DR, but as a GM I'm not sure I want to roll every time the baddies are hit.

I prefer DR over AC, and with some way of bypassing DR as well.

But as someone who likes mechanical tinkering, I'm curious about alternatives.

I'm rather happy with most combat systems if they're fun to plan, but at heart I'm a attack/parry/DR kinda-guy.

Fixed DR is fine with me. Rolling damage is enough, I wouldn't even mind dropping that. Yes, a way to bypass DR is fine with me, but that should be luck or ability of the attacker, not a botched roll of the defender.

Another option is the RoleMaster system, where different armor has different table entries for hits and criticals. Sadly HARP went another way with armor just adding to the defensive bonus.

In the end, I want to see a difference between agile fighters without armor vs. plate tanks on one side, and finesse fighters with foils and daggers vs. claymore-swinging brutes on the other side.
Not that they neccesarily have to be balanced, though.

I like the Rolemaster way too, but it's too complicated for most gamers. As a second choice I'd go with anything that lets me roll damage dice, preferably ones that explode like in Hackmaster.

I'm coming around to armor-as-DR after playing a lot of Exalted, where "soak" is subtracted from raw damage total before you roll for final damage.  I'd like to try it in D&D, but my gaming group are notoriously hard to get to go along with any tweaking.

I'm a straight up armor as DR sort of guy, all the way.  Beyond even classes and levels (two things I hate in gaming) I hate the 'AC' concept as implemented by D&D the most.

Fuck me sideways with a fork if I ever claim to like it in any way, shape or form.

I can understand your players, Corvus. Integrating DR as the default armor mechanism will result in a lot of changes. You need another defense mechanism, ways to bypass DR etc.

Also, to hit bonuses already outstrip AC enough that making ACs lower across the board runs the risk of seriously overpowering the already incredibly nice Power Attack feat.

I'm actually fond of Palladium's Armour Rating as the chance that they hit your extra hitpoint suit instead of you.

Better still, Armour as DR with very low values and linked batches of extra hit points.

DR's nominally nice, but I have a hard time with any DR type system that uniformly deducts a value regardless of other factors if the armor provides less that complete coverage.

It's easiest to get around this with hit location systems (which can complicate things), but there are a few other methods as well. Most sacrifice something, though.

Honestly, from a realism standpoint, I've always been more happy with a combination of both, like GURPS3's PD/DR, or SDC Palladium's AR/SDC, or the Fallout/SPECIAL combination of penalty to-hit and DR%.  

But for my present system, I jsut went with an aggregate Defense score that acts as a to-hit penalty.  I might tack on an additional DR component, to keep with the source game that is it's strongest inspiration.

I'm pretty happy with Iron Heroes, which uses a scaling defense score that determines how hard you are to hit and armour with random DR (that can be boosted with class abilities and feats).

I'm a fan of the old Dragon Warriors armour bypass system.
 
Armour had a fixed value (1-5) and the weapon had a armour bypass die randing from D3 (club) to D12 (Halberd IIRC) with a sword having D6.
If you sucessfully beat the opponents defense, you rolled your AB die vs his armour. Greater than his Armour and you do full weapon damage (which was a fixed value), lower and it bounces off for zero.
Critical hits always bypassed armour, and IIRC a very high strength rating got you a +1 on AB rolls.

IIRC, Burning Wheeeee uses something like this, too.