The Ætherium, the Ambience

As mentioned under “What is Magick?”, 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 “Ætherium”, but more frequently and informally referred to as the “Ambience”, – although this is not to be confused with the Ætheric Sphere itself. This continuous field of energy 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 from moment to moment or place to place, but can build in intensity or ebb away with the mercurial timing of Nature Itself.

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.


High & Low Mana

With the ebb and flow of the eddies and currents of the Ambience, some parts are bound to either become saturated by especially heavy flows or back-eddies feeding deep, rich pools of mana, while other parts are left spiritually thin and nearly mana-dry as the currents or tides carry the mana away.

The mana-rich zones are called “high mana” areas, and the mana-dry zones are “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 or wider, 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 the Arts 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 drift along maintaining contact 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 here, 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 MGT 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 MGT 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 made of a little power, where the flow is low he may simply have to take a little more time to draw the desired POT to cast.

For every point of the practitioner’s MGT 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 MGT scores of 13 or lower.

  • Every point of POT in the Ambience by which a practitioner is casting a charm in a High Mana area subtracts one (1) from the DV for the casting and drops the Wind cost by one (1) point.
  • Every point of POT in the Ambience by which a practitioner is casting a charm in a Low Mana area adds one (1) to the DV for the casting and increases the Wind cost by one (1) point.

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 for the day for a given location the first time any magick is cast there. 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.

The POT of the Ambience is of primary importance to the practitioners of magic in the GM’s world, as it can very well change the CTM’s of their charms, depending on what they wish to accomplish.

Every time a charm is cast at a POT equal to the POT of the Ambience at a given location or greater, the Ambience for (HRT) feet in radius surrounding drops by one (1). 

Every time a charm is cast at the same location before the POT of the Ambience has a chance to rebound, it continues to drive the Ambience POT down, also reducing the POT that can be drawn at once into a given casting within the normal CTM.

Each point of POT of the Ambience so used takes one (1) minute to return.

The practitioner must move to a location where the radius of the effect of his casting does not overlap the first if he wishes to escape these conditions/consequences.

It is a good idea for the GM to plot the major movements and distributions of mana on his game maps when designing the game world 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 which by nature are not in tune with the environment, as their infinite industry and driving need to mold the world about them over time destroys the wild and fragile spirit of the mana generated by the living, natural world. This might cause the accumulation of a differential, a negative modifier of (d5) points each year 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 flowing back and forth 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 do so are 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.


The Effects of Civilization on the 

Ambience for Druid & Witch Mana

As long as Witch and Druid (any) characters remain in the wilderlands, regardless of where they go, the all-encompassing elemental nature of the mana their Arts rely upon remains evident. Far from the madding crowds, it lies always immediately at their fingertips. There is life in even the most desolate of environments. Normal standards of high- and low-mana areas do not apply to them.

While they can benefit from high-mana areas in the same manner as any Wizard, the normal penalties of low-mana areas do not apply to them.

For Witches this is supplemented by the presence of worshippers following the Green Lords and the Olde Ways in the manner described for Mystics, above.

Low-mana areas are similarly irrelevant to Mystics.

For the purposes of all Druids and also Witches, the filthy dens of the races of men all count as low-mana areas. The greater the population, the greater the corruption of the natural world and the more difficult works of magick depending upon Nature’s power becomes, most specifically in a town, village or even settlement, within precincts that are dedicated to public buildings and facilities, businesses and residences. These penalties arise from a sense of place too well defined and beaten into the earth, from the mass of dead brick and stone buildings, dead hewn timber, the cast-off filth of the residents, and the emotional refuse of the people who have claimed the town or city as their home.

Those modifiers should not necessarily be applied when the character is located in an isolated country citadel, castle, or manor, or in any dependent village with a population of 50 or less. These modifiers are applicable to larger villages and towns, and especially walled ones in particular, especially those built on the Roman model, in which the streets are not only paved but laid out in strict a grid.

The table following shows the degree by which the mana of Nature has been pushed away from such locations.

Village/Town Setting Ambience
Casting in village or hamlet w/population of: (d5)
less than 50 (––)
Up to 50 (—)
50 to 100 -1 to 5
100 to 500 -6 to 10
500 to 1,000 -11 to 15
Casting in city or town w/population of: (d10)
1,000 to 5,000 -16 to 25
5,000 to 10,000 -26 to 35
10,000 to 20,000 -36 to 45
20,000 to 30,000 -46 to 55
30,000 to 40,000 -56 to 65
40,000 to 60,000 -66 to 75
60,000 to 80,000  -76 to 85
80,000 to 100,000 -86 to 95
100,000+ -96 to 100

The “(—)” entry for small villages indicates that the established settlement is small enough and sufficiently rural by nature that the Ambience throughout is the same as that found in the surrounding countryside, levying no penalty.

Up to a population of 1,000 the internal setting of the village or town is still sufficiently rural for some of the power of Nature to seep through. Indeed, for those of greater talent, the penalties applied in some villages or hamlets may not even count as “low-mana”, when the ranges that count for such are adjusted according to MGT, as previously defined.

Penalties levied for these settings should always be eased outside their walls, or at the nearer edges of the surrounding dependent fields that provide their food (GM’s discretion), at a rate of roughly 1 point per yard of distance.

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 Wind 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.