Extract from 'A Primer on Spell Structure' by T. H. Marthins
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Spells can be structured in a variety of ways depending on who is casting them, the magic system they are using, the form of spellcasting they are employing, and the type of spiritual matter they are utilizing.
This diversity makes describing the structure of spells rather complex. For simplicity, this book will focus exclusively on the Thaumic Standard System, which provides a widely accepted framework for understanding spell construction.
In the Thaumic Standard System, spells are structured into two main sections: the Mantle and the Core. All spells are constructed using spell runes, which are explained in detail on pages 3–4.
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MANTLE
The Mantle is the outermost section of a spell construct, acting as its protective shell. It is essentially a layer of raw personal mana wrapped around the Core. The primary function of the Mantle is to:
* Shield the spell from interference by environmental mana.
* Protect the spell’s structure from negation magic or similar disruptive forces.
While the Mantle enhances stability, it is not strictly necessary for the construction of a functional spell. Most spells are not exposed to sufficient environmental mana to warrant a Mantle. However, in disciplines where external interference is common—such as Illusion Magic—the use of a Mantle is highly recommended.
In addition, higher-level spells often have built-in protection mechanisms, rendering an external Mantle redundant in many cases.
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CORE
The Core is the heart of a spell, where its mechanics and casting processes occur. It is divided into three distinct layers:
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1. Outer Core
2. Inner Core
3. Matrix
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MATRIX
The Matrix is the innermost layer of the Core and serves as the spell’s foundation. It contains the base programming, including the spell’s Element (e.g., Fire, Water) and Effect (e.g., Explosion, Healing). The mana required to fuel the spell is also stored here.
The Element and Effect are encoded using spell runes. Attempting to modify these runes mid-cast is highly risky, as even minor alterations can destabilize the spell construct. This risk is especially pronounced when working with volatile elements. For example, editing the Matrix of a Fireball spell while casting could result in a catastrophic explosion, harming the caster and their surroundings.
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OUTER CORE
The Outer Core defines the mechanical properties of the spell. Parameters such as size, shape, velocity, trajectory, and others are encoded in this layer. These parameters determine how the spell interacts with the physical world.
Unlike the Matrix, the Outer Core allows for limited adjustments during casting, provided the caster possesses sufficient skill and knowledge. For instance, a caster must understand the spell’s structure and know which spell runes to modify in order to achieve specific effects. Most ATR-certified mages are trained to safely make such adjustments, enabling them to fine-tune spells on the fly.
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INNER CORE
The Inner Core serves as a secondary layer of programming within the Core. It allows for the addition of secondary matrices, elements, or effects, effectively expanding the spell’s complexity. For example, a Fireball spell could incorporate an Air element to enhance its speed or add a secondary effect like Burning.
Like the Mantle, the Inner Core is not mandatory for constructing functional spells. However, it becomes essential for advanced spells, particularly those classified as Tier 4 or higher. These spells often require multiple elements or effects to function effectively, making the Inner Core a critical component at higher levels of spellcraft.