A point of confusion has arisen concerning the effects of Perdo spells on creatures with Magic Might. As an example, please consider the spell Lay to Rest the Haunting Spirit:
Say we have a ghost with a MM score of 20 and a full 20 points to draw on. Casting the spell LTRTHS at level five, with 21 penetration, apparently reduces the MM by five, but what aspect of its might is reduced? The SCORE (which would lower its resistence and make it much easier to effect each subsequent time the spell is cast) or the point pool (which effects its ability to use powers, but not its resistence)?
This obviously makes a big difference in how such encounters progress.
I interpretted it as reducing the Might score, which may in turn reduce the number of points remaining, as points cannot exceed score. After all, Demon's ETERNAL Oblivion sounds pretty final, which I don't feel is accurately captured in the other interpretation.
Each subtraction from say DEO (L:5) would reduce it by 5 pts, but would not reduce the creatures resistance at all.
Its kind of like the old D&D rules for dragons. The breath weapon is based on the cretures hit points. If an enterprising party snuck in on a dragon, they could do a LOT of damage in the first round. If you based his breath weapon off that, his first breath of fire could do 5 or 10 points...
BUT.... if the dragon wakes up and hits the party with say 88, and 75% of the party dies, well that makes dragons much more difficult...
By doing it this way (Score/point), you are not penalizing the creature for being hit...How would you like it if your spells did 10% damage because you had been hit???
I would say that the the Might Score is unaffected and what is reduced is the Pool. It seems logical that the pool which naturally diminishes and gets replenished would be the one that gets affected. That means the creature keeps resiting at full strength, but it might start losing some of its abilities if it doesn't have enough Might, so there is still value in hitting it with those Perdo spells.
I looked through the text andi Ibeliev that the text for the spells did not get tranlated to the new edition with the seperate terms might score and might pool.
But if we're voting. I think that reducing might score is going to make games more fun than reducing might pool. I also think that a creature with a might pool of zero should not be destroyed, it should just be out of juice.
Considering the consequences of the two interpretations:
If we go with the MM score reduction reading, we greatly increase the value of having a range of low-level high-penetration DEO type spells. You start with a level 1, 29 penetration version for a few rounds, than amp it up to the level 5, 24 penetration version, and so on. It also means that even low powered magi could, with sufficient cleverness/forethought and some good rolling, actually do some damage against more powerful creatures.
If we go with the point pool reduction reading, we find that our low-level characters are going to have a much harder time dealing with MM rated foes, and even if they are able to amp up their DEO with confidence point and vis usage (Wizards Communion etc) and make a dent of worth in the scaly hide of Bifron the Badass, it would be quite expensive for them to do it a second or third time, and chances are they'll pretty quickly reach a point where they can't do anything to further their cause.
All things considered, and despite my desire to have bad-ass-vampire-ghost-demon-fairy-trolls who scare my players, I think you're right that the "slow whittling down" interpretation sounds like more fun.
If you lower the score, does it replenish across time?
Not much value, since all you can do is tire out the target. Maybe that would let you run away from it?
It seems natural that one of the abilities that would be dropping might be the resistance to magic. I mean, wouldn't it be odd if you could completely annihilate something's ability to do anything mystical, other than its ability to defend itself?
I think that the problem here might be that resistance was tied to score, rather than pool, in the first place. I can't think of any reason why that should be the way things are arranged â€” I'd love it if someone could let me know what the rationale is for that rule.
"If you lower the score, does it replenish across time? "
I see nothing to indicate that the Score replensihes over time. On page 191 it says that the creature's Might pool refreshes over the course of a day. The absence of a rule would then lead one to believe that reducing the Score is a permanent thing. That's probably not the way it's intended IMO.
"Not much value, since all you can do is tire out the target. Maybe that would let you run away from it?"
That depends, what power level is the creature versus the players? Beginning PCs probably shouldn't encounter a creature with a Might higher than 20. A DEO level 10 would only require 2 succesful castings. It might be a bit tough to do so, but with a good aura, shouting, grand gestures, certain Virtues, vis, any of these things can help the wizard pull it off. Hitting it only once might convince the creature to run off, it just lost half its Might after all. After the second casting it's dead, for good. For a creature that potentially is immortal, that's pretty major. Finally, no one said battling Demons and Dragons was easy or safe.
"It seems natural that one of the abilities that would be dropping might be the resistance to magic. I mean, wouldn't it be odd if you could completely annihilate something's ability to do anything mystical, other than its ability to defend itself?"
Not really, an unconscious Magus is just as magically resistant as he was when awake, he just can't fast cast improvised defensive spells.