As mentioned in the Introduction, mana is the spirit and power of magick. As a general force, it is seen by the trained practitioner to permeate and overlay every corner of the Mortal World, constituting a vast continuous energy field known as the “Ambience”, but also as the “Ætherium” – though not to be confused with the Ætheric Sphere itself. That continuous field flows through and about the mortal worlds of RoM in “ever-changing currents and eddies”, as noted. Because it is not static but flows about, the amount of power flowing about free to grab and use on a moment’s notice is not always the same, but can build in intensity or ebb away from time to time and from place to place.
To facilitate handling this, a numerical rating system is used for measuring the Ambience and for reflecting changes in its intensity, called Potence (POT), the same that the power, effect or complexity of substances and/or obstacles created by the skills of others which the PC’s can encounter in play, a lock’s or trap’s complexity, a beast’s venom, the alcohol a character consumes, the virulence of a disease, a plant’s poison, or an alchemist’s drug or brew, and the like, as discussed under “Task Resolution”.
This makes it more easily integrated into the process of casting magick. Unlike the other purposes for which POT is used, when used to measure the strength of the mana present in the Ambience it can actually fall into negative numbers.
With the ebb and flow of these flowing eddies and currents some parts of the Ambience are bound to either become saturated by especially heavy flows or deep back-eddies feeding pools of mana, while other parts are left spiritually thin and nearly mana-dry as the currents or tides carry the mana away. We call the mana-rich areas “high mana” areas, and the mana-dry areas “low mana” areas. Some of the mana streams move like young rivers, as fast as 15 mph or so, while other flows are more like an ocean current and just as wide, moving no more quickly than 3-4 mph. The actual course and width of the slower, wider flows tend to fluctuate only slightly over time, perhaps only by a few feet from side to side per year. Some mana pools or backwaters grow or shrink in extent a couple times a day as the mana fills them just like a tide (and similarly subject to the moon) and then runs out again, with the pools themselves perhaps also drifting along but only slowly, again maybe only a few feet along a given course per year.
Schools of magick and the strongholds of powerful masters of magick are commonly built on such sites to take advantage of this when it occurs. The floating castle or castle in the air of the fairytales is the perfect vehicle for allowing the practitioner of magick to move along with a high mana concentration when he has found one that is moving slowly enough to be practical for his purposes.
In a high mana area the effect of the Wizard’s bond to his Power and its effects on those around him, as detailed in this chapter, in the trade description, and elsewhere, are heightened. In a high mana area reality is sharper, clearer and more intense, colors are brighter, shadows deep and velvety, lights dazzling and glorious, darkness Stygian and impenetrable, sounds are clearer and more resonant, music is sweeter, silence rings with foreboding, and emotions are sharper and more poignant, with greater depth. Mundane folk will shy away from all such areas. They are just “too much” all the time.
In a low mana area just the opposite will be true, all the aspects of life and living are squelched, colors dulled, tastes flattened, the world lying under a blanket of monotonous sameness – and mundane folk have no trouble living in such locations, especially if their SPT scores run below average. If the low mana area has been there a long time and the residents have lived in it long enough, low SPT scores may well be the norm as the residents acclimate to that environment.
What qualifies as the “normal” range of mana saturation depends on the individual’s talent. Everything is relative, as the Laws of Magick inform us.
For the average practitioner with a MGA of 14, anything higher than a 14 POT in Ambient power is considered “high mana”, and anything from 12 down is considered “low mana”.
For every 2 points of the practitioner’s MGA above 14, the POT in Ambience beyond which an area is considered high mana (14) or low mana (12) drops by 1 (one).
The greater the talent, the more that can be done with a little power, where the flow is low he must simply have to take a little more time to draw the desired POT to cast.
For every point of the practitioner’s MGA below 14, the threshold beyond which the Ambience in an area is considered high mana (14) or low mana (12) rises by 1 (one).
It takes a richer Ambience for the poor in talent to practice the Arts.
The lesser scores discussed here apply to those who practice the “lesser” skills of the Hedge Wizard and Hearth Witch, the Cunning Man and Wise Woman, who are allowed to have MGA scores of 13 or lower.
As a rule of thumb, and to make the use of the principle easier, the GM should roll 3d10 to determine the POT of the Ambience the first time any magick is cast in a given location for the day. Assuming that the GM has not placed any extraordinary features of the Ambience in the locale to affect it, that POT should remain the same all day, except perhaps for a crest of tide around noon and another at midnight.
For the next day a d5 should be rolled, a result of “1” meaning the POT has dropped by (d5) points, or of “5” meaning the POT has risen by (d5) points, otherwise it stays the same.
The GM should flip a coin or otherwise determine whether to add the number of days since the last change in POT to the daily die roll or subtract the number of days from it to ensure that there is always a change every few days. Should the characters move any appreciable distance (10 miles or more), the GM should always roll a new 3d10 to determine the POT of the Ambience in the new location.
It is a good idea for the GM to plot the major movements and distributions of mana on his game maps when designing the gameworld prior to play, especially if he wants any of them to be stable in position, or to drift only very slowly. Both low and high mana areas should be fairly uncommon, though not exactly rare. The GM should think of the mana as a great ocean that envelopes his whole world, with few major currents or backwaters that would affect the casting of magick, and just as few archipelagoes where the mana has been drawn away. Taking a look at the currents of the Real World oceans can provide a good idea of the scale involved. For a more dynamic standard for the currents, the changes in the jet stream over North America between summer and winter provide a good example.
Low mana areas are much more likely to occur on or near the largest settlements of humanoids that not in tune with their environment, as their infinite industry and driving need to mold the world about them destroys the wild and fragile spirit of the mana generated by the living, natural world over time. This might cause the accumulation of a differential, a negative modifier of (d5) points every year or every 2 or 3 years, to be applied to all rolls to determine the POT of the Ambience in that locale. The POT of the Ambience would rise by one for every rod (5 yards) one travels from the outskirts of the town until the full normal POT rolled for the area prevails once again.
The GM might make the mana flows travel along with the weather, being partly responsible for it. Indeed, the power unleashed in a great storm may well indicate the temporary presence of a high-mana area, the very means by which Nature bleeds that Power from Spirit down into the World of Flesh to achieve more stable levels, much like the action of lightning in the Real World. It might also be made to vary seasonally, the rate of flow slowing and mana levels in general dropping during the winter months when the world sleeps, only to rise and quicken again when the sap rises in the spring. Because its distribution should be somewhat unstable (always traveling from the area of greatest concentration to the area of least concentration), the GM should have at least the backwaters or eddies of mana move and circulate, shrink and grow, if not having the currents slowly shift from side to side. The rate at which they will do this will be entirely up to the GM.
To keep the paperwork down, the slower the shifts the easier these changes are for the GM to handle. One simple form of variance is to have them reverse their pattern of movement from one season to another, much as the winds on our planet do from summer to winter, bringing the monsoon rains to such places as India and Indonesia. As weather fronts get pushed up against great obstacles like mountain ranges, the mana may pool there as well before rising in concentration great enough to spill over. This might bring about strange or very extreme seasonal weather, after the fashion of “wizard weather” as it is called in the Thieves’ World books edited by Lynn Abbey and Robert L. Asprin. Of course, the GM can always base movements of mana upon random throws of the dice. What better way to reflect the caprices of Nature?
Of course the movements of mana about the material world cannot affect Mystic trade characters in the least, though traveling in lands where there are no worshippers of his faith to prop up his power is the equivalent of low mana for him.
All towns are low mana areas for Witches and the members of the Druid trades. The greater the population, the lower the mana. The immediate presence of plant as well as animal life should indicate if Nature’s power is accessible, so the Witch may find a little garden area here or there within a city where the mana is not AS low as it is in the surrounding neighborhoods.
Casting magicks Druid, Witch, or Wizard magicks in a low mana area is always more taxing. Regardless if they have the patience to wait and gather the POT they desire to power their dweomers, doing so is simply harder than normal. To reflect this, the END cost to cast any magick in a low mana area is higher.
The reverse is also true. When casting in a mana rich or high mana area, the END cost is lowered.
This is detailed under “The Cost of Casting Magick” to follow.
Of course the magick-wielding character is always free to completely sidestep the vagaries of Nature and the limitations of the POT of mana available from the Ambience by drawing from his own life-force and using his own END for the POT of the magick, in addition to the normal cost for casting the magick, or unlocking a source of mortal mana to tap instead, or creating a Touchstone to use. All these topics are detailed in later passages.