Making magic hurt - mechanics for grittier magic in Pathfinder RPG
We've been debating and discussing mechanics for capturing the grittier magic that exists in the current Dark Golden Age time period of Gondal. Thematically, most of the elements of grit revolve some soft of self-sacrifice for the caster to empower their spell-casting ability. As I've been thinking about these mechanics, I have come to the point that they can be grouped into two different impacts - at the time of preparation or at the time of casting.
At Preparation
Wizards memorize. Clerics, druids, paladins and rangers prepare. Sorcerers and bards ready. Each of the spell-casting classes does something each day that enables their spell-casting powers. At this point, the caster can experience some sort of hardship that makes preparing her spells challenging. It also usually means the caster can mitigate the results in some fashion.
Ability damage - One possibility is for there to be some sort of ability damage. Constitution makes the most sense since it does not directly impact casting ability but does impact survivability. In the transition from 3.5 to Pathfinder, ability damage became much rougher in that a character only recovers one point per day. In a party without access to Lesser Restoration (Cleric 2, Druid 2, Paladin 1), this mechanic could be somewhat rough if the ability damage is more than one per day as the character will eventually reach zero if spells are prepared every day.
Damage - Another idea revolves around the character receiving some degree of normal or nonlethal damage. This is much easier for a character to handle, especially if the party includes a good-aligned cleric. The issue becomes an annoyance but is probably only a burden at the time of spell preparation. The difficulty is lessened but the reminder is still there. While less painful for the players, it may make the challenge of being a spell-caster too little.
At Casting
In order to make the changes to magic more prominent, the most obvious way is to alter it at the time of casting. No player will forget that magic is more challenging to do when their character is impacted every time she wishes to cast a spell. The challenge with these mechanics is that they increase the amount of time it takes for a player to complete their turn.
Making spells harder to cast - Casting spells could be made more difficult by requiring a Concentration check to successfully cast. Concentration checks in Pathfinder RPG are now a function of class level and related ability score for that class. A sorcerer adds Charisma to her class level to make a Concentration check. If the check succeeds, the spell is cast as expected. If the check fails, the spell might fail or the caster could suffer damage of some sort (or even both).
Reducing the effects of spells - Instead of directly hurting the caster, the effects of the spell could be reduced. The two most direct ways are to reduce the save DC or to reduce the caster level. Caster level affects almost every spell in either range, duration, or effect. For those spells that are not affected by caster level, the save DC could be reduced instead.
The Big Question
It's possible to test these mechanics to the point that they could be fine tuned and confirmed as to not being overwhelming. However, does there need to be just one mechanic that is the official one for the rulebook? Or do you think a setting could have multiple mechanics that allow for a group to use the mechanic that will best fit the specific style of game they deisre?
