Magicians can perform magic because of the nature of mana. Mana is fueled by life and rises and falls in different locations and times. We are in the Sixth World and mana is rising overall each year except for the Year of the Comet when it spiked and later dropped. From a game mechanic point of view the increase of mana allows for today’s magicians to be just as effective as magicians in 2050 using a fetish. Mana is very sensitive to metahumanity and psychoactively charged by emotions, violence, and events charged with meaning and psychological significance. Repeated use of magic performed by a Tradition or through the use of geomancy can aspect mana towards supporting that Tradition. Widespread worship, prayer, and meditation can create a spiritual oasis as well. An area can also become a domain and aspected towards a specific magical skill like a master enchanter’s forge who loves what he does used over decades could develop additional layers of aspect for joy, creation, artificing, the enchanter, and the enchanter’s tradition.

Mana is also sensitive to the environment of the mundane world getting warped by pollution or radiation or naturally aligned to certain types of magic by powerful physical variables like the area around volcanoes being aspected towards fire magic and friendly to fire spirits. Feng shui, geomancy, and geomasonry are able to manipulate how the mana flows and what aspect it might have.

From page 30 Street Grimoire:

“A background count is a measurement of a variance from normal of mana levels in the area. Arcane scholars have developed a scale to measure the strength of these areas, ranging from –24 to 24, with 0 considered normal mana levels. A negative value relates to lower-than-normal mana available to be used for magic (meaning mana ebbs and voids). A positive value relates to mana that has been aspected in some fashion, making it harder to control unless your aspect overlaps with it (domains and warps). Regardless if it’s a positive or negative number, we use the absolute value in determining how it affects the Awakened’s use of magic.”

So what this means is that any BC that isn’t 0 that hasn’t been acclimated will impact either in a positive or negative fashion an awakened entity or astral denizens magical abilities. A place with less mana than normal will have a negative rating which means that ALL MAGIC will be penalized. A place with more mana than normal will have a positive rating and could help or hurt an awakened entity or astral denizen depending on many different factors. It is very possible for a positive BC to provide aid for one magical test and harm the next.

“Acclimated individuals are able to ignore background counts, but aligned people take it one step further. They are able to completely mesh with the aspect of a domain, getting a boost from the mana in that area.”

Acclimation is something that an awakened being or astral denizen can develop while spending time in that type of mana environment. Since most Universities in most areas focus on the Hermetic Tradition one could assume that any magician who achieved an undergraduate degree at such an institution would have achieved a certain degree of acclimation to a knowledge and hermetic environment. In the NAN the dominant BC at an University would be knowledge and shamanistic and in China knowledge and Wuxing for other examples. The awakened with a rarer tradition would still not gain the benefits of alignment to the dominant tradition and so would have to work harder than their compatriots privileged with alignment to the background count.

From page 31 Street Grimoire:

“The most powerful mana lines or events that have emotional or magical significance to most of humanity. Examples include the five sacred mountains in Chinese lore including T’ai Shan, where the great dragon Lung lives (Rating 15), The Great Cairn line in Tír na nÓg (Rating 14), The blast sites of Hiroshima and Nagasaki, Nazi death camps, or the Native American Re-Education Center at Abilene (Rating 13).”

The problem with this comes in with a later bit in which a greater than -12 or +12 BC causes Stun damage every combat turn. How does the Dragon Lung survive his home? Obviously he has an insane Willpower as a Great Dragon but with this rule he would be pummeled into unconsciousness in a day as the rule specifically says even if it is a domain. No matter how high his rating eventually the dice will fail. So, there must be some technique that Lung is able to do to survive this and that he is able to provide to his spirits, awakened servitors, and others unless he exists utterly alone in his home except for mundanes!

“It can take weeks or months of exposure to become acclimated to the background count before his skills aren’t affected by it. Generally speaking, you should plan on one week of exposure per rating point of the background count.”

I have an house rule I am still polishing up that will help quantify what BC a starting character would be acclimated to prior to play.

From page 32 Street Grimoire:

“A background count impose a negative dice pool penalty equal to its rating for all tests linked in any way to magic (such as spellcasting, summoning, and skill tests that use active adept powers such as Killing Hands or Improved Sense). The exception to this rule are background counts from domains, where a tradition, person, skill group, or skill may be exempt from the penalty as they are used to or aligned with the domain. Dual-natured creatures or purely astral creatures take a negative dice pool penalty to all actions equal to the background count. Again the exception of a domain can apply to specific types of creatures or spirit types. Pre-existing active foci, sustained spells, quickened/anchored spells and rituals are reduced by the background count. If they are reduced to 0 or less, spells fizzle, wards and rituals collapse, foci deactivate. A foci cannot activate while under the influence of the background count. Anchored rituals and quickened spells if they have not expired revive themselves at 1 point of Force per hour, up to their preexisting Force. Preparations triggered while within a background count have their potency immediately reduced by the background count. Adepts may use a Simple Action to turn on or off a passive power in cases where penalties from background counts might exceed bonuses from their powers. Background count makes Assensing, Astral Perception, and Astral Combat more difficult to do. Impose a negative dice pool penalty for tests associated with these skills. When attempting to track an astral entity through an area where the background count is higher than the target’s Force or Magic Rating, the tracker loses the astral link at the point of the background count.”

Many questions should immediately pop out at you upon reading this. Does a spirit summoned by a magician share his alignment or acclimations? Does a preparation or focus gain the benefit of alignment or acclimation from its creator or owner? Does it acclimate on its own or is there something the magician can do or must do? What if the quickened spell was made before the magician was acclimated? Wouldn’t an astral tracker benefit from tracking a target if it enters her domain which lets say she created?

“ACCLIMATED

This is a benefit of the Home Ground quality (p. 74, SR5). The quality allows characters to ignore the customary background count of an area, and only count half of the background count tied to temporary events.”

Well, earlier the book says that acclimation can be gained by any magician just by spending some time there. This kind of makes that option of the Home Ground Quality pretty weak if two weeks hanging out in a neighborhood acclimates you. It would make much more sense if Home Ground provided alignment for the magician. After all if you’re taking this quality you have a very strong tie to the area to the point where it is a key part of who the character is and what better way to show that than that over the years or decades you’ve been living in a neighborhood you’ve become so in tune with the astral realm and its mana that you and it naturally align together. Your home is a part of your magic now.

“ALIGNMENT

The background count is applied as a positive modifier to the limit tied to the skill or skills for an Awakened character aligned to a domain. For example, a Wiccan shaman trying to conjure a Force 4 spirit within a Hag Bolette ring (Rating 3 aligned to the Wiccan tradition) will have a Conjuring limit of 7 (4 + 3). A background count with an absolute Rating value of 12 or greater is dangerously powerful, regardless if it’s from a domain or void. Anyone magically or astrally active in any way (dual natured, astrally perceiving, casting a spell, active adept power, etc.) takes background count – 12 Stun Damage each combat turn they are exposed to it. They can resist this damage with a Willpower Test.”

Alignment can be an on/off thing like a domain of fire may align with a hermetic casting a flamethrower spell and the catholic priest throwing a censor with incense imbued with a preparation to unleash a fireball but penalize a shaman performing a Rain making ritual.

There are domains so great that an unprepared mage could be knocked unconscious by their sheer power, and there are great flaring bursts of mana called mana warps, which are more powerful than even the most powerful of domains.

This implies that a prepared mage could handle a powerful domain!

So, that covers the rules from Street Grimoire. A little known and lightly covered bit with a BC forming temporary spikes in potency is important as is the rule for alleviating half of the temporary BC because of acclimation.

From Aetherology:

Any area of magic lower than normal is termed as having a negative background count. Places that have higher-than-normal positive background count do not affect a magician’s ability to cast magic unless it’s been psychoactively fixed, which brings me to my second point. The second thing you should understand is mana is very sensitive to man. His emotions and his exploits can disrupt the accessibility of magic. From a rock concert to a violent robbery, from toxic waste to smog, mana becomes psychoactively charged, making it difficult to use if your magic is not aligned. A positive background count that is affected by this charge is called aspected. If it’s based on a physical place with some emotional or psychological significance, the aspected mana is tied to a domain.

This brings up something that is a bit of a contradiction to previous rules in Street Grimoire which state that positive BC must be aspected. With this added bit it makes sense that most any place with higher mana is more sensitive to life, man, and the environment making it very likely to aspect. Also later on it contradicts the information in Street Grimoire about mana warps which in Street Grimoire on page 33 it states are areas with -16 to -20 BC while in Aetherology and in other parts of the Street Grimoire it states that higher levels of mana are called mana warps. Later on in Aetherology it mentions that certain high BC areas are very attractive to awakened animals. One would think that the animals if attracted would not be penalized or harmed by the higher mana and must gain some benefit otherwise why would they be attracted to those areas?

Musings:

A bit of fluff in previous editions is about how shamans don’t like to spend time in polluted or irradiated areas as spending too much time might be dangerous to them and push or tempt them into toxic shamanism. This could be a danger of acclimation and alignment with a BC is that the psychoactivity of mana is a two way street which is described in the Street Grimoire as various things like dragon lines purifying the environment or domains controlling denizens to pick up litter for examples. The mana can influence your emotions and viewpoints over time. This should be roleplayed and could be a good explanation for a quality gained in character generation or in play.

For example a neighborhood focused on learning, academia, and knowledge that a character has the home ground quality may have become more studious and respectful of knowledge in general because of her home. A Desert Wars magician might have spent years in mana soaked in the Battle aspect and as a consequence become more martial in outlook and more likely to use violence as a tool. Where does the experience and where does the mana aspect start and stop?

I also like the idea of aspected mana having multiple aspects or layers. A Spiritual place may provide the prime aspect for a hidden church in Aztlan and a secondary aspect might be Fear caused by the emotions of the worshipers about getting caught by the Nahuatl and sacrificed. A tertiary and temporary aspect might pop up from a lover’s spat taking place in the church a few hours earlier leaving traces of Anger. In this case the priest would be aligned to the Spiritual aspect and acclimated to the Fear aspect but vulnerable to the Anger until it faded away. Since the priest is aligned to the prime aspect he would gain the increased limit for his magic, acclimated to the secondary aspect so it would have no effect on his magic, and the tertiary aspect since it was temporary and he was acclimated or aligned to the more dominant aspects he would only face half the BC from it rounded down as a penalty.

I am working on a system to allow for a magician to gain at character generation various acclimations to different types of mana that they would have developed based on their character background. It utilizes a variation of the Contact system to work and just like contacts the magician will need to occasionally spend some time and effort in order to get exposure to that aspected mana and maintain their acclimation.

It is also important to realize that 0 is normal. If BC is a bell curve it should be -1 to +1 at least two thirds of the time.

Here are some previous rules and viewpoints I had developed prior to the release of the Street Grimoire with various alternatives and house rules.

BC in 5e

Primer on Mana

An Abstract from the Journal of Practical Thaumaturgy