Thaumaturgy in GURPS

Thaumaturgy uses Realm-based syntactic magic, detailed in Thaumatology ch.6. Mana, as described in the basic magic rules, is not a concern. However, Magery(Thaumaturgy) is a requirement. This advantage can be learned at any time, and thaumaturges can range from Magery 0-4, with the vast majority existing between 0 and 1. Going beyond that level requires significant dedication of time and energy, either studying transcendental mechanisms, practicing the art, or both. In game terms, Magery cannot be purchased with bonus points; it can only be gained through study or practice. Magery level is added to Realm skills and is a prerequisite for each level in the Realm advantages (a thaumaturge cannot earn Vital Matter 2 without Magery 2).   Thaumaturgy uses the rules for threshold-limited magic detailed on Thaumatology p.76, rather than the normal FP cost. The base threshold score is 30, with a threshold recovery of 1 point every 3 hours (or 8/day). Thaumaturges can take advantages to improve their threshold score and recovery.

Thaumaturgic Realms

The thaumaturgical Realms are based off the four common states of matter, as understood by Duurnic scholars, plus additional Realms for living organisms and the metaphysical. Transforming an object between different states of matter requires knowledge of the current state, the target state, and any intermediary states. For example, turning ice to steam requires knowledge of solid matter, liquid matter, and gaseous matter.   Thaumaturgy cannot affect sapient minds directly, nor can it do anything that the practitioner does not have an intricate understanding of. For example, a thaumaturge with sufficient understanding of solid matter might be able to create a stone wall from the dirt, but they probably could not create a working internal combustion engine. The level of complexity that a thaumaturge is capable of depends on their technical understanding of whatever they are trying to do, but increasing complexity causes a greater risk of dangerous mishaps.   Each level within a Realm costs 12 points.

Available Realms

• Vital Matter
  • Pertains to living things, such as plants, animals, humans, and beyond. Only affects physical biology and cannot be used for mental effects
  • Example actions: Healing, Controlling plants, Biological enhancement
• Solid Matter
  • Pertains to inanimate matter in a solid state
  • Example actions: Turning lead to gold, Digging a trench
• Liquid Matter
  • Pertains to inanimate matter in a liquid state
  • Example actions: Diverting a river, Creating a burst of acid
• Gaseous Matter
  • Pertains to inanimate matter in a gaseous state
  • Example actions: Accelerating the wind, Creating breathable air
• Plasmatic Matter
  • Pertains to inanimate matter in a plasmatic state
  • Example actions: Throwing fireballs, Diverting lightning
• Astatoma
  • Pertains to the Astatoma and the Veil
  • Example actions: Reading a place's impression in the Veil, Mending a hole in the Veil

Levels

For the physical Realms (everything except Astatoma), there are four known levels of understanding. Each level grants a practitioner an increasing command over the Realm in question. The levels are pure abstraction. In practical terms, plenty of thaumaturges have varying levels of command over different aspects of the Realms they focus their studies on.   For the physical Realms, the levels are:

1. Fine manipulation
   • A person at this level could use Astatomatic energy to make something within a particular Realm do something that it is capable of. For example, someone with Vital Matter 1 could speed a person's natural healing. This is sometimes seen as simply a lesser version of Control.
2. Control
   • A person at this level could use Astatomatic energy to make something within a particular Realm do something it is not normally capable of. For example, someone with Vital Matter 2 could directly heal someone's wound (albeit temporarily).
3. Transmutation
   • A person at this level could use Astatomatic energy to transform something within a particular Realm in an unnatural way, even to something from another Realm if they have both Realms at sufficient levels. For example, a person with Vital Matter 3 could give a person gills or turn a horse to stone (if they also have Solid Matter 2).
4. Creation
   • A person at this level could create something of a particular Realm, using pure Astatomatic energy. For example, a person with Vital Matter 4 could create a human body out of seemingly nothing but thin air (though thaumaturgy cannot create true life, as far as anyone is aware).

  Hypothetically, an additional level exists for physical matter, sometimes called Gnosis. With this hypothetical level, a practitioner would be capable of rewriting the rules of reality for a particular realm, making a person functionally a deity.   For Astatoma, there are only two available levels:

1. Detection and measurement
   • Anybody with Magery(Thaumaturgy) can detect significant changes in the Veil, but a person with Astatoma 1 can garner much finer measurements of the Veil, as well as gain additional information about places and people by reading the Veil.
2. Fine manipulation
   • A person at this level can manipulate the Veil and the Astatoma in small and subtle ways. For example, a person with Astatoma 2 could mend a small tear in the Veil or manipulate someone else's use of Astatomatic energy.

For the Astatomatic Realm, several hypothetical levels exist, allowing a practitioner to control, transmute, and create Astatomatic energy more directly. Additionally, a final hypothetical level for this Realm also exists, where a practitioner could rewrite the rules of the Astatoma. This is so far beyond the cope of what is known to be possible that it is purely the realm of pulp fiction.

"Laws" of Thaumaturgy

Thaumaturgy has a number of rules that limit its practice. Some of these are hard rules of reality, discovered from endless experimentation and study. Others are closer to practical guidelines, intended to keep novice thaumaturges from destroying themselves or their surrounding city blocks by dabbling with things better left alone.

Law of Equivalent Exchange

The first rule of thaumaturgy is sometimes referred to as "equivalent exchange," other times as an ominous warning about the price of power. Either way, thaumaturgy cannot create something out of nothing, and everything that is done with thaumaturgy carries a price. Even at level 4 of any given Realm, a practitioner is not actually creating something out of thin air. They are using Astatomatic energy to reshape the molecules and energy of their surroundings into whatever they will. In most cases, this price is obvious and direct, but practitioners that attempt monumental displays of power often find that the consequences of their actions extend far beyond anything they imagined.

Law of Information

The second rule is simply that thaumaturgy within the Realms of physical matter cannot directly provide information that the practitioner does not already know. No matter how hard a thaumaturge tries, they cannot tell the future. They also cannot scry beyond the limits of their senses (though they could enhance their senses, using Vital Matter). The major exception to this rule is the Astatomatic Realm, whose practitioners can detect and measure the Veil in their immediate vicinity. This can give information beyond what a practitioner knows, since the Veil carries impressions of the world around it, but these impressions are often surreal and abstract, more impressionist painting than photograph.

Law of Sapience

The fourth law states that thaumaturgy cannot directly target a mind or soul. Thaumaturges cannot directly create mental effects or hallucinations for a target, and it cannot influence a target's mind. While there are many stories of thaumaturges enthralling towns of people towards their dark bidding, this is sheer fantasy.

Law of Viopoeia

The final law states that thaumaturgy cannot create true life. While it is possible for thaumaturgy to create functional bodies of animals and even humans, no thaumaturge has ever managed to truly create another living being. Whether this is because of the inherent complexity of life or because of a missing metaphysical component, no one truly knows. The closest thaumaturgy has gotten to true life has been the creation of plants.

Thaumaturgic Shaping

The use of thaumaturgy is called "shaping," named as such because practitioners are shaping the energy of the Astatoma to perform their art. Shaping requires a thaumaturge to have levels in each applicable thaumaturgic Realm sufficient to perform the effect they are intending. For example, a practitioner that wishes to create a thunderstorm would require at least Gaseous Matter 3 and Liquid Matter 2, in order to transmute gaseous water into its liquid form and manipulate the water in the air to create a thunderstorm. If they also wanted to control the ensuing lightning, they would also need Plasmatic Matter 1 or 2!   Before the practitioner rolls their Realm skill to determine the results of their shaping, they must establish the parameters of the effect.

Parameters

Each usage of thaumaturgical shaping has parameters that should be established before the practitioner makes their skill roll. How these are calculated is detailed below, but a thaumaturge should state their desired effect and intentions as specifically as possible. The results of the skill roll will determine how close the product of their shaping is to their intention. Any parameter based on margin of success that is left open will automatically be taken at the highest possible level. See Thaumatology p.181 for more information on these calculations.

Base Cost

The base cost of a shaping is twice the level of the highest-level Realm involved, plus the level of any other Realms used. This cost is applied to the thaumaturge's tally, per the threshold-limited system on Thaumatology p.76.

Range

Range applies a skill penalty to shaping attempts. For every yard between the practitioner and the target (or the closest edge of the target area of effect), a -1 penalty is applied to the skill roll. Note that for many combat shapings, the range is calculated to the origin of the attack, not the target.

Duration

Duration is determined by margin of success. The effect of shaping lasts a length of time corresponding to margin of success, as close to the intended duration as possible. For example, if a thaumaturge intends for their effect to last a week (MoS 5) but they get a margin of 2 on their roll, the effect would instead last an hour. If they instead get a margin of 6, the effect would last a week, despite MoS 6 normally granting 2 weeks of duration.

Area of Effect

Area of effect is determined by margin of success. If the margin of success is insufficient to cover the intended area, the shaping may still take partial effect if that would make sense. Otherwise, the shaping attempt fails.

Damage, Damage Type, and RoF

Damage is determined by margin of success. The practitioner's intended damage type and rate of fire is also taken into account. If the margin of success is insufficient to deal the intended damage, the shaping attempt deals as much damage as the MoS allows.

Healing

Healing is determined by the margin of success. For every 3 points in the margin, the practitioner can heal 1d of HP. However, thaumaturgical healing is notoriously fickle. The HP healed by a thaumaturgical spell is lost once the duration of the spell is over. In effect, the healed wounds reopen as if the injury that caused them happened again.

Ability Modification

Ability modifications are determined by margin of success. If the MoS is insufficient to apply the desired effects, the shaping may take partial effect if possible. Otherwise, the attempt will fail.

Weight Affected

If the weight that a shaping effects is relevant, then the skill roll receives a penalty based on the weight of the object the practitioner is targeting. This penalty is based on the Weight Affected Modifiers Table on Thaumatology p.243.

Multiple Targets

If a shaping affects multiple targets, the practitioner's skill roll receives a penalty based on the Multiple Target Modifiers Table on Thaumatology p.243.

Complexity

More complex shapings apply penalties to the practitioner's skill roll based on the Multiple Constituent Modifiers Table on Thaumatology p.243.

Shaping Time

Generally, shaping times are calculated as a number of seconds equal to the (highest-level Realm involved + 2). However, this may differ.

Other Rules

• Thaumaturges can take a penalty of -3 to the skill roll to halve the shaping time of an effect. They can also double the casting time to receive a +1 to the skill roll.
• Thaumaturgy is easier in areas where the Veil is weaker. Skill rolls related to shaping get bonuses from +1 to +5 in such areas. However, the results may be more unpredictable or dangerous.
• If a practitioner gets a critical fail on a thaumaturgic skill roll, they must roll using the Thaumaturgy Critical Fail Table, rather than the normal spellcasting critical fail table.
• The "Aura" optional rule (Thaumatology p.76) for threshold-limited magic is in play. A thaumaturge using the Astatoma Realm can discern another practitioner's "aura"
• The "Safer Magical Excess" advantage for threshold-limited magic is banned.
• The sacrifice of sapient beings can provide powerful bonuses to shaping. Apply a bonus to the Realm skill roll equal to half the modifier from the Multiple Targets Modifier Table on Thaumatology p.243, with a minimum bonus of +1, based on the number of sacrificed individuals. The same modifier unhalved is applied to the tally cost of the shaping. If the practitioner is distracted while the sacrifices are being performed, the Astatorum that they are gathering slips from their grasp, often with devastating effects. The sacrificed individuals must be unaware, unresisting, or helpless for this bonus to apply. Sacrifice is incredibly powerful, but it comes at a high cost. Treat any shaping where sacrifice is performed as if the practitioner got an 18 on the critical fail table, even if they succeed at the skill roll (the effect still proceeds as normal for whatever result they get). Extreme sacrifices may have even more dire consequences, at the GM's discretion.