Regarding...
Also, the sword is an excellent parrying weapon when compared to a hafted weapon. This is glossed over in D&D.
Coincidentally, recently I encountered the assertion that the axe was a poor defensive weapon.
Should that difference affect the parry bonus? Perhaps the swords get +2, axes and other hafted melee weapons (axes, maces, hammers) get +1 or even 0?
armor makes you easier to be hit but makes you more difficult to be damaged.
I see that the "easier to be hit" is reflected in your penalties to parry for medium and heavy armors, and apparently the parry penalty you give medium and heavy armor replaces the cap on dexterity modifier in the rules? (since you later state that heavy armor still gets a DEX, in contrast to the armor table (in the Basic rules) showing that heavy armor AC is not affected by dexterity modifier). I prefer that the weight and bulk of armor affects the dexterity modifier to defense (whether "Armor Class" or your "Parry") rather than caps that modifier or causes it to be ignored. Using a penalty rather than a cap will mean that
every character is easier to hit when it is in heavy armor than when it is not, and that increasing dexterity will always benefit defense, regardless of armor worn. The dexterity 18 fighter in heavy chain or plate should more adroitly dodge blows than the dexterity 10 fighter in the same armor.
regarding the modification to parry bonus when it's the only item in one's hands:
I do think the X1.5, round down rule for held items looks more appropriate than doubling. I would ask you to clarify whether the parry bonuses for held items stack. If they don't, then I think the increase for holding the one item alone is too much, because without stacking but with the single-item increase, a fighter with only a shield is two points better in parry than one with a shield and a sword, independent of actions taken in combat.
With respect to my suggestion that weapon size matter for "parry", with large size weapons better than small size ones, you responded:
I think the extra size from the wielder offsets the advantage to using a larger weapon. It is easier to hit a large creature/object they also can parry better. To make it simple these factors could offset each other.
Seems reasonable that the parry modifier for weapon size could simply offset a creature size modifier to AC/parry. Except size modifiers surely are already built into the stat blocks, so adding additional parry for this proposal would be appropriate - unless one decides the current AC also accounts for that.
Regarding armor - thanks for clarifying about DR 2,3,4 relating to die size:
Well with the armors I was thinking of dice types. 2 = 1d4, 3 = 1d6, and 4 = 1d8. I also wanted to make the values low enough so that with magic armor bonuses the DR does not become too onus.
Perhaps magic armor bonuses should be considered deflection and therefore modify Parry rather than DR.
If you want to roll dice/have variability in DR, how about d3 for light, d4+1 for medium, d6+2 for heavy to start with?
What do you think of my observation that the conventional AC may account for the wielding of a melee weapon, which can be accommodated by either:
a) the parry modifier to a weapon should be normalized to 0 for the melee weapons, while small and light weapons (e.g.: dagger) get -1, pole weapons (e.g.: spear, halberd) get +1,
or
b) the base Parry for a human becomes 6, to account for adding both Proficiency and weapon parry bonus.
You could go 2/4/6 for the DRs I suppose, but I worry about magic making the ACs to high and making HP last too long. perhaps 1/3/5 may work..
I think you mean magic making the DR, rather than AC, too high? Does my suggestion above about applying the magic bonus to Parry deal with this issue?
As far as HP lasting too long - this is of course going to depend on the specific DR value(s) and on the nature of attacks the characters suffer in the campaign. The math has to work differently if we simply translate a fixed AC to a fixed DR. But because in D&D damage per attack tends to increase with level of encounter, going to an Armor as DR system risks the behavior mentioned by [MENTION=7989]Wrathamon[/MENTION], that the armor-wearer becomes less vulnerable than in the unmodified rules to low-damage attacks, but less protected in the attacks of foes that deliver higher damage per attack. A certain degree of this makes sense - a dagger wielded against a plate armored champion in melee would have a hard time doing any real damage at all.
One possible mitigation for the fact that armor-as-DR doesn't reduce hit probability, so in this system armor helps less than AC against high-damage attacks: perhaps DR can be proportional to proficiency bonus?
At its most simple:
light armor DR = prof
medium = 2*prof
heavy=3*prof
This does mean the dagger-armed (d4 damage) PC cannot expect to hurt the mail armored NPC (DR=6 at levels 1-4) at all unless
- the PC makes critical hit
- the attack has significant damage bonuses of some sort (ability modifiers, magic enhancement, circumstantial or class feature bonuses,
- the attack qualifies for additional damage dice (e.g., Sneak Attack)
- there is explicit provision for circumventing armor (perhaps within critical hits)
Another idea: factor in degree of success - increase damage or die size proportional to the amount one exceeds the needed to-hit roll, and/or make critical hit dependent upon degree of success (possibly in addition to on natural 20). I imagine that will slow the game down with more math.
