The Cautious Mind: Rego (Creo) Mentem 20
R: Personal, D: Sun, T: Ind
The caster of this spell controls his mind to naturally adapt a more cautious, evaluative state when considering and committing to courses of action. As a result, he rolls one fewer botch die whenever making a stress die roll. This can mean he rolls no botch dice. However, as a result of his caution, he is less inclined to quick action: His quickness is penalized by 1 when under the effects of this spell. The Creo requisite ensures that the mind made a better extension of itself as opposed to simply timid.
Base 5 (Incline a person to a particular response, in this case caution), +2 Sun, +1 Creo requisite.
Design notes: There is no Hermetic Limit against reducing botch dice, so it seemed at least permissable to try (unlike say fatigue levels). Rego mentem (control a mind in a natural way) seemed the most appropriate guideline. The Creo requisite helps ensure that the mind still operates at a high capacity, rather than an enchanted one. The penalty to Quickness is largely there for game balance. Otherwise a magus could use this spell 2 seasons a year during daylight for lab work and every time he goes on an adventure, without incurring warping.
What do my sodales think? I'm unsure as to what the exact appropriate base level would be, but 5 seemed fair enough according to the guidelines. Is the -1 quickness for -1 botch dice a fair tradeoff?
IMO, no. The die roll is the element of chance and fate, and it doesn't really play to the Base you're using. I don't think something that mitigates botch dice can apply to any base guideline that exists, period.
There are multiple avenues to avoid botching. Make an item, whether a lesser one or fully invested device. Master spells, that reduces botch dice to zero. I've said it before elsewhere, I think there would be very many mastery tractatus around for common spells. Take a familiar and make a stronger Golden Cord. I talk about all of these possible options for mitigating risks associated with magic, first, because, as designed an presented, the spell is one that affects a magus, so I take that's the goal, to reduce botch dice for anything for a magus, whether it is magic or abilities. They are also available to the player after the character has been developed and in play. In addition to those options I've already mentioned there are the virtues available at character creation: Flawless Magic, Cautious Sorceror, and Cautious with Ability. There may be one other that I'm forgetting at the moment. Some of those options for mitigating botch dice risk might be available after character creation by pursuing a Mystery Cult.
Going back to my first point, though, is that the die roll is the element of chance, and if you think botching is to prevalent in your saga, maybe exploring how botches occur is a better approach. If such a spell were possible, it gives the Mentem specialist an even greater amount of power than he already has.
Improve the safety of your lab
Stop casting in a hostile aura
Stop casting in dangerous conditions (no, atop a speeding horse that doesn't like your gift, in a snowstorm, while engaging a dozen armed knights is NOT a good place to cast your spell)
Learned Magicians (in Hedge Magic: the Revised Edition) can eliminate botch dice at a rate of one per magnitude for a single ability, so if you're going to allow Hermetic Magic to do that I think I'd bump the base guideline up a bit and/or place restrictions on how generally it removes botch dice. (In addition to this being one of Learned Magicians' "things" they also have their Techniques as difficult arts (meaning they advance at the same rate as an ability. Being very restrictive on how generally a spell applies is also a Learned Magician "thing", so I might not restrict the applicability quite as harshly as a Magician's is, especially if the base guideline boost is substantial.)
Thanks for the responses. You all have made very valid points. I think I'll bury this spell. It does seem a bit overpowered. Do you think there are some kernels here worth salvaging? Using CrMe or ReMe beneficial effects other than permanently raising stats?