…Is deciding why to target one over another.
Poison for example, is a very ambiguous term that represents any of a number of foreign contaminants that attack a body in any of a number of ways. Hallucinogens affect the mind of the victim, creating confusion. Other poisons paralyze the muscles of the lungs or heart to cause asphyxiation. Others cause cells to self-destruct.
Whether we’re talking Third or Fourth Edition Dungeons & Dragons, poison tends to target Fortitude, occasionally targeting Will for hallucinogens. I imagine the design decision to go one way or another is usually dependent on the “flavor” of the poison and its general effect on the victim. Some problems arise with this.
The Mind-Body Problem as it relates to philosophy examines the difference between the mind and perception, and physical reality. Do you believe in the dualitic concept of “Mind over Matter?” For example, can will and determination overcome the frailties of the body? Or is the mind a mere plaything of a living organism, subject to its needs?
Using ideas borrowed from all over the place, I created the Seven States Cosmology to answer the mind-body problem with a question: “What makes you think we’re only made of two parts?” Looking at different defenses now, I wonder if maybe I’ve made them irrelevant, considering how many power sources I’ve made available to players.
My system is peculiarly additive, rather than selective or divisive as many other systems. A player heaps on and focuses bonuses rather than paying lip service to the system via flaws and passive vulnerabilities. Weakness are emergent and must be discovered through gameplay, rather than being rigidly defined from the get-go.
One example of overcoming such a problem can be found in how I would treat undead like the vampire: rather than giving a vampire a passive vulnerability to sunlight or fire, I would give certain classes a specific power to create a fire vulnerability in undead creatures. Exploiting the vulnerability becomes the responsibility of the aggressor.
Under those circumstances, I can’t see how it makes sense to create a myriad of passive defenses for the player to keep track of — the best I can think of is perhaps two: one for armored defense and one for unarmored defense. Even that seems a bit… I don’t know, preachy? It may require additional over-thinking.
I think the main question I have to ask is this: “why, given the many and varied options for proactive offense, should there be more than one type of passive defense?” I think it makes more sense to have a single defense score the defender can modify on the go than to have different passive options for the attacker to choose among.
It’s sort of like a situation wherein a challenger chooses the game but the defender chooses the battlefield. It’s like, the one advantage of being the defender. Given the circumstances, it seems odd to me that the attacker would be the one to define the defense being targeted. That … might just be me. Just sayin’.