So I am thinking about my own homebrewed system, and am wondering how to implement damage. I am considering two types of system here:
Damage is rolled separately (base on weapon), and success of the hit roll plays little or no part in determining damage (Most versions of D&D, Savage Worlds etc.)
Damage is dependent on how much you exceed your opponent's Defense (Fate, Chimera, Shadows of Esteren). In Shadows of Esteren, damage is your attack's roll + weapon damage - opponent's defense.
My questions are:
From a game design perspective, is there a reason to favour one over the other?
While basing damage on degree of success "feels" realistic, are there any pitfalls associated with it? Generalizations based on existing games which use this type of mechanic are welcomed.
Assumptions
Hit Points and Damage are abstract, as in D&D. Though I do not see the difference if Hit Points really represent bodily wound or just a combination of luck, skill and toughness. Specifically, I am interested in how the number is generated, not what it means.
What I am looking for
This is some analysis I haven't verified, and I am putting here as an example of what am I looking for.
Using "damage as another roll", two opponents with vastly different to-hit can still hit each other for the same amount of damage - the chance to hit, and the probability for high or low damage is decoupled. Say A has only 10% chance of hitting B, but do 2d10 damage. B may have 50% chance to hit A, but only still do 2d10 damage. Hence perhaps I could say that A has a ghost of a chance to kill B because each hit - if he does hit - he does 2d10 damage.
The second case, say A has only 10% chance to hit - and for simplicity sake, say for every 1 percentile he succeeded by (say roll d100 under chance to hit), he does 1 damage. Hence A cannot do as much damage to B as B will be to do A, so A is less likely to be a threat, even if he does hit. Unless the system has some sort of exploding dice roll. And B, going by the system, could hit with more damage,making the to-hit chance even more important.
Stuff like this.