Dungeon crawl, dungeon crawl, hack and slash away,
Oh what fun it is to find some monsters for to slay, hey,
Dungeon crawl, dungeon crawl, hack and slash away,
Oh what fun it is to find some monsters for to slay.
Sneaking down the hall, checking all the doors,
They say we've got some balls, they say we're treasure whores,
Disarm all the traps, keep formation tight,
What fun it is to go and sing a slaying song tonight, oh
Dungeon crawl, dungeon crawl, hack and slash away,
Oh what fun it is to find some monsters for to slay, hey,
Dungeon crawl, dungeon crawl, hack and slash away,
Oh what fun it is to find some monsters for to slay.

Something else along the same lines. I realize this isn't 100% consistent with the above, but it's still a work in progress.

Filtered mana casters:
Casting speed is limited by the environment. On leylines or outflow points (Earthnodes) where available mana is higher, casting speed will likewise be higher. Thus an filtered mana caster will always be looking for the “high spot” in available power to draw from. Daily maximum is effectively unlimited, but risk of failure increases as more power is used between rest breaks. Most places in most environments will yield 2-3 PPs/round, but a cluster of outflow points whose radii of effect overlap could yield 10-20 PPs/round or higher. This isn’t too risky soon after a rest, but can easily be lethal to the caster if he or she is tired.

Rendered mana casters:
Every single act, including casting, is a representation of your God. Therefore every single casting requires an Appeasement roll in order to acquire the necessary PPs. Extraordinarily good or bad Appeasement rolls will shorten or lengthen casting time, and could even affect subsequent actions/spells. Note that sacrifices and other actions can add bonuses or penalties to Appeasement. Also note that while available power is only limited by the power of your God, asking for more than the minimum necessary is pushing your luck, and can also affect Appeasement rolls. Risk is also tied to Appeasement rolls. How much Appeasement results are dependent on die rolls vary with whether your God is a proponent of order or chaos.

Personal mana casters:
Casting is fast, with the default being instantaneous. Available power is determined by Self Mastery skill, and in theory you could use all of the day’s power on a single instantaneous spell. But on the other hand, while power is instantly available, the more power you use at a time, the higher your risk of failure and the more likely the consequences are to be bad. Thus Personal mana casters will tend to stick to low cost spells when possible, and when high cost spells are needed, choose to take as long as conditions permit to cast the spell. The above example of using all of the day’s power instantaneously is very much a desperation move, and could easily render the caster permanently insane.

Anchored mana casters:
Casting speed is one round per component used. Thus a Anchored caster will always be looking for the most powerful possible components, so that the most powerful spells can be cast in a minimum amount of time. PPs beyond what is needed for the casting will be expressed as Fortean effects. Expect Anchored casters to be very grudging about using components that are even a single point more powerful than the minimum needed. As with Filtered mana users, Anchored mana users’ risk increases with the amount of power used since the last rest period.

Hybrids of 2:
Filtered/Anchored:
Speed is whichever is faster. Risk is amount of power used between rest breaks.

Filtered/Rendered:
Speed and risk are dictated by the granting entity.

Filtered/Personal:
Speed is limited by environment. Risk is power used per amount of casting time

Anchored/Personal:
Speed is one round per component. Risk is power used per amount of casting time.

Anchored/Rendered:
Speed and risk are dictated by the granting entity.

Rendered/Personal:
Speed and risk are dictated by the granting entity.

Hybrids of 3:
Filtered/Anchored/Personal:
Speed defaults to instantaneous. Risk is power used per amount of casting time.

All other hybrids of 3:
Speed and risk are dictated by the granting entity.

This is where I currently am regarding insanity as a result of spellcasting.

Everyone has a "mental fragility" or just "fragility" rating, expressed in a number of ranks. The more fragility ranks you have, the more quirky you will be under normal conditions, and the easier it is for events to push you over the edge. Note that events having nothing at all to do with magic can increase your fragility and/or push you over the edge. The first time you deal with a death, the first time you encounter an undead monster, anything that your brain wants to refuse to process as "the world is not supposed to work like this!" Even a bad breakup of an emotional relationship can do it, although thankfully that's pretty rare.

But specifically to spellcasting, this is what I currently have regarding a fumbled casting. In all but one case I'll be using Rasyr's labels from "The Ecology of Magic." Note: "Fortean effects" are defined as random minor magical effects. Rainbows, a tiny thunderstorm right over your head, doves flying out of your butt, whatever. Also note that "Anchored mana" is mana trapped inside of physical objects, eg spell components. The following tables apply in 50% of all casting fumbles, the other 50% follow the normal rules for the game system you're using.

Filtered mana:
01-40 You are aware of everything. Spend 1-5 rounds coming to terms with the fact that you can’t possibly process it all, before reluctantly returning to reality.
41-70 Random Fortean effects in a d100/2’ radius. Possible minor damage to those in the radius.
71-90 You are now subject to giggling fits and occasional hallucinations. +25 to attempts to cure you. Add 1 Fragility rank.
91-00 You suffer from delusions. -25 to all attempts to cure your insanity. Add 2 Fragility ranks.

Rendered mana:
01-40 50% chance to become catatonic for 1-10 rounds any time you roll UM 01. Permanent until cured. +50 to attempts to cure your insanity.
41-70 Random Fortean effects in a d100/2’ radius. Possible minor damage to those in the radius.
71-90 You are unworthy of your God. You aren’t even worthy of your party members. +25 to attempts to cure you, if they can get you cured before you commit suicide. Note that whether or not this is actually true is beside the point, you still believe it. Add 1 Fragility rank.
91-00 You are The Ultimate Avatar Of Almighty Gawd™. Let’s hope your God agrees with you. -25 to all attempts to cure your megalomania. Add 2 Fragility ranks.


Personal mana:
01-40 50% chance to panic for 1-10 rounds any time you roll UM 01. Permanent until cured. +50 to attempts to cure your insanity.
41-70 Random Fortean effects in a d100/2’ radius. Possible minor damage to those in the radius.
71-90 Paranoia. +25 to attempts to cure you. Add 1 Fragility rank.
91-00 Multiple personality disorder. -25 to attempts to cure you. 50/50 chance for each of those personalities to be paranoid, 10% chance to be violently so. Add 2 Fragility ranks.

Anchored mana:
01-40 You now have Tourette's Syndrome.
41-70 Random Fortean effects in a d100/2’ radius. Possible minor damage to those in the radius.
71-90 You have acquired a random phobia. Roll vs. SD at -25 to act rationally in its presence. +25 to attempts to cure your insanity. Add 1 Fragility rank.
91-00 You are nothing but a quivering, crying little blob of goo. -25 to all attempts to cure you, not least because you’re terrified of the doctor. Add 2 Fragility ranks.


My current take on Fragility is that all spellcasting uses the random roll, plus your skill in the spell, plus one per rank of fragility. In other words, the crazier you are, the more likely you are to have your spells work. Your ability to choose the right target may suck, but wow your spells work! This goes along with the rationale that you have to be temporarily insane to cast spells at all, and also does the GM a favor by giving him an endless supply of "monsters" in the form of spellcasters who have gone insane, and who are more deadly than ever before as a consequence. It also challenges parties to find ways to keep a crazy spellcaster on tap, and just turn him loose when needed. The bad news is that all the risks associated with caster insanity also apply to your healer.

Comments?

I tried writing a reply and the board wouldn't take it. Perhaps I got too long winded.

One of the reasons I like risking sanity is because it allows you to individualize consequences of failure. You can have megalomania be a risk for one type of caster, paranoia for another, kleptomania for yet another, etc.

Another thing I liked about the idea is that it helps put casters and fighter types on an even footing. You think it takes courage to be a fighter? Dude, all you risk is your life. Better than having your friends hunt you down and kill you out of pity.

And the rationale I have chosen allows for the idea that the more insane you get, the more powerful caster you become. So from the player's point of view, what's the risk? You may become a powerful caster in the party, but you may become a boss monster for the GM. I know more than one player who would love that idea.

Ever since I worked on the HARP rewrite a decade or so ago, I have thought mana sources and the skill of using them needed a good going over.

I think that however many sources of mana there are, each of them should have a separate and distinct skill of tapping that power (thus acquiring "power points"  or whatever label you choose), and that none of those skills should be a "magical skill." For example, power from the Gods should be sourced by the skill of Appeasement, an Influence/Social skill. Power drawn from the natural flow of the planet or plane you're on should be sourced by Thaumatology, an Academic/Scientific skill.

Anyone have any thoughts or comments on the subject?

I took RM2, houseruled it until it was pretty much the game I wanted, and then skipped RMSS and RMFRP entirely.

And from what I've seen on the ICE forums, I suspect that my answer was the rule rather than the exception. Because of that, the publishers had a major problem in that it had "splintered" so badly that it was nearly impossible to make anything acceptable to a majority of their fanbase.

Or at least that's my understanding. I certainly could be wrong about that, it wouldn't be the first time and won't be the last.